diff --git a/doc/build/changelog/changelog_07.rst b/doc/build/changelog/changelog_07.rst
index 7b28f5f230..314a6b9a0a 100644
--- a/doc/build/changelog/changelog_07.rst
+++ b/doc/build/changelog/changelog_07.rst
@@ -3,10 +3,22 @@
 0.7 Changelog
 ==============
 
-                
+
 .. changelog::
     :version: 0.7.10
-    :released: 
+    :released:
+
+    .. change::
+        :tags: orm, bug
+        :tickets: 2624
+
+      The :class:`.MutableComposite` type did not allow for the
+      :meth:`.MutableBase.coerce` method to be used, even though
+      the code seemed to indicate this intent, so this now works
+      and a brief example is added.  As a side-effect,
+      the mechanics of this event handler have been changed so that
+      new :class:`.MutableComposite` types no longer add per-type
+      global event handlers.  Also in 0.8.0b2.
 
     .. change::
         :tags: orm, bug
@@ -52,7 +64,7 @@
 
     .. change::
         :tags: orm, bug
-        :tickets: 
+        :tickets:
 
       Fixed bug mostly local to new
       AbstractConcreteBase helper where the "type"
@@ -68,7 +80,7 @@
 
     .. change::
         :tags: orm, bug
-        :tickets: 
+        :tickets:
 
       A warning is emitted when lazy='dynamic'
       is combined with uselist=False.  This is an
@@ -76,7 +88,7 @@
 
     .. change::
         :tags: orm, bug
-        :tickets: 
+        :tickets:
 
       Fixed bug whereby user error in related-object
       assignment could cause recursion overflow if the
@@ -140,7 +152,7 @@
 
     .. change::
         :tags: bug, sql
-        :tickets: 
+        :tickets:
 
       Fixed more un-intuitivenesses in CTEs
       which prevented referring to a CTE in a union
@@ -261,7 +273,7 @@
 
     .. change::
         :tags: engine, bug
-        :tickets: 
+        :tickets:
 
       Fixed the repr() of Enum to include
       the "name" and "native_enum" flags.  Helps
@@ -294,7 +306,7 @@
 
     .. change::
         :tags: sqlite, feature
-        :tickets: 
+        :tickets:
 
       Added support for the localtimestamp()
       SQL function implemented in SQLite, courtesy
@@ -320,7 +332,7 @@
 
     .. change::
         :tags: bug, mysql
-        :tickets: 
+        :tickets:
 
       Updated mysqlconnector interface to use
       updated "client flag" and "charset" APIs,
@@ -347,7 +359,7 @@
 
     .. change::
         :tags: mssql, bug
-        :tickets: 
+        :tickets:
 
       Fixed bug where reflection of primary key constraint
       would double up columns if the same constraint/table
@@ -385,7 +397,7 @@
 
     .. change::
         :tags: orm, feature
-        :tickets: 
+        :tickets:
 
       The 'objects' argument to
       flush() is no longer deprecated, as some
@@ -511,7 +523,7 @@
 
     .. change::
         :tags: orm, feature
-        :tickets: 
+        :tickets:
 
       Added new flag to @validates
       include_removes.  When True, collection
@@ -548,7 +560,7 @@
 
     .. change::
         :tags: orm, bug
-        :tickets: 
+        :tickets:
 
       Fixed bug in relationship comparisons
       whereby calling unimplemented methods like
@@ -558,7 +570,7 @@
 
     .. change::
         :tags: bug, sql
-        :tickets: 
+        :tickets:
 
       Removed warning when Index is created
       with no columns; while this might not be what
@@ -568,7 +580,7 @@
 
     .. change::
         :tags: feature, sql
-        :tickets: 
+        :tickets:
 
       Added new connection event
       dbapi_error(). Is called for all DBAPI-level
@@ -578,7 +590,7 @@
 
     .. change::
         :tags: bug, sql
-        :tickets: 
+        :tickets:
 
       If conn.begin() fails when calling
       "with engine.begin()", the newly acquired
@@ -593,7 +605,7 @@
 
     .. change::
         :tags: mssql, feature
-        :tickets: 
+        :tickets:
 
       Added interim create_engine flag
       supports_unicode_binds to PyODBC dialect,
@@ -603,7 +615,7 @@
 
     .. change::
         :tags: mssql, bug
-        :tickets: 
+        :tickets:
 
       Repaired the use_scope_identity
       create_engine() flag when using the pyodbc
@@ -657,7 +669,7 @@
 
     .. change::
         :tags: bug, mysql
-        :tickets: 
+        :tickets:
 
       Fixed bug whereby get_view_names() for
       "information_schema" schema would fail
@@ -724,7 +736,7 @@
 
     .. change::
         :tags: orm, feature
-        :tickets: 
+        :tickets:
 
       Added "no_autoflush" context
       manager to Session, used with with:
@@ -797,7 +809,7 @@
 
     .. change::
         :tags: orm, bug
-        :tickets: 
+        :tickets:
 
       Improved the "declarative reflection"
       example to support single-table inheritance,
@@ -932,7 +944,7 @@
 
     .. change::
         :tags: engine, bug
-        :tickets: 
+        :tickets:
 
       Added execution_options() call to
       MockConnection (i.e., that used with
@@ -952,19 +964,19 @@
 
     .. change::
         :tags: engine, feature
-        :tickets: 
+        :tickets:
 
       Added some decent context managers
       to Engine, Connection:
-      
+
           with engine.begin() as conn:
               <work with conn in a transaction>
-      
+
       and:
-      
+
           with engine.connect() as conn:
               <work with conn>
-      
+
       Both close out the connection when done,
       commit or rollback transaction with errors
       on engine.begin().
@@ -1031,7 +1043,7 @@
 
     .. change::
         :tags: examples, bug
-        :tickets: 
+        :tickets:
 
       Altered _params_from_query() function
       in Beaker example to pull bindparams from the
@@ -1076,7 +1088,7 @@
 
     .. change::
         :tags: orm, feature
-        :tickets: 
+        :tickets:
 
       Added "class_registry" argument to
       declarative_base().  Allows two or more declarative
@@ -1084,7 +1096,7 @@
 
     .. change::
         :tags: orm, feature
-        :tickets: 
+        :tickets:
 
       query.filter() accepts multiple
       criteria which will join via AND, i.e.
@@ -1115,14 +1127,14 @@
 
     .. change::
         :tags: orm, bug
-        :tickets: 
+        :tickets:
 
       Fixed bug whereby hybrid_property didn't
       work as a kw arg in any(), has().
 
     .. change::
         :tags: orm
-        :tickets: 
+        :tickets:
 
       Fixed regression from 0.6 whereby if
       "load_on_pending" relationship() flag were used
@@ -1200,7 +1212,7 @@
 
     .. change::
         :tags: feature, sql
-        :tickets: 
+        :tickets:
 
       Added "false()" and "true()" expression
       constructs to sqlalchemy.sql namespace, though
@@ -1283,7 +1295,7 @@
 
     .. change::
         :tags: sqlite, bug
-        :tickets: 
+        :tickets:
 
       removed an erroneous "raise" in the
       SQLite dialect when getting table names
@@ -1544,17 +1556,17 @@
 
       polymorphic_on now accepts many
       new kinds of values:
-      
+
         - standalone expressions that aren't
           otherwise mapped
         - column_property() objects
         - string names of any column_property()
           or attribute name of a mapped Column
-      
+
       The docs include an example using
       the case() construct, which is likely to be
       a common constructed used here. and part of
-      
+
       Standalone expressions in polymorphic_on
       propagate to single-table inheritance
       subclasses so that they are used in the
@@ -1571,7 +1583,7 @@
 
     .. change::
         :tags: orm, feature
-        :tickets: 
+        :tickets:
 
       Added new value for Column autoincrement
       called "ignore_fk", can be used to force autoincrement
@@ -1581,7 +1593,7 @@
 
     .. change::
         :tags: orm, bug
-        :tickets: 
+        :tickets:
 
       Fixed bug in get_history() when referring
       to a composite attribute that has no value;
@@ -1662,13 +1674,13 @@
 
     .. change::
         :tags: feature, schema
-        :tickets: 
+        :tickets:
 
       Added new support for remote "schemas":
 
     .. change::
         :tags: schema
-        :tickets: 
+        :tickets:
 
       MetaData() accepts "schema" and "quote_schema"
       arguments, which will be applied to the same-named
@@ -1678,13 +1690,13 @@
 
     .. change::
         :tags: schema
-        :tickets: 
+        :tickets:
 
       Sequence accepts "quote_schema" argument
 
     .. change::
         :tags: schema
-        :tickets: 
+        :tickets:
 
       tometadata() for Table will use the "schema"
       of the incoming MetaData for the new Table
@@ -1692,7 +1704,7 @@
 
     .. change::
         :tags: schema
-        :tickets: 
+        :tickets:
 
       Added CreateSchema and DropSchema DDL
       constructs - these accept just the string
@@ -1700,7 +1712,7 @@
 
     .. change::
         :tags: schema
-        :tickets: 
+        :tickets:
 
       When using default "schema" with MetaData,
       ForeignKey will also assume the "default" schema
@@ -1734,7 +1746,7 @@
 
     .. change::
         :tags: bug, schema
-        :tickets: 
+        :tickets:
 
       Fixed bug whereby TypeDecorator would
       return a stale value for _type_affinity, when
@@ -1743,7 +1755,7 @@
 
     .. change::
         :tags: bug, schema
-        :tickets: 
+        :tickets:
 
       Fixed bug whereby "order_by='foreign_key'"
       option to Inspector.get_table_names
@@ -1781,7 +1793,7 @@
 
     .. change::
         :tags: postgresql, feature
-        :tickets: 
+        :tickets:
 
       Added create_type constructor argument
       to pg.ENUM.  When False, no CREATE/DROP or
@@ -1836,14 +1848,14 @@
 
     .. change::
         :tags: bug, mysql
-        :tickets: 
+        :tickets:
 
       Unicode adjustments allow latest pymysql
       (post 0.4) to pass 100% on Python 2.
 
     .. change::
         :tags: ext, feature
-        :tickets: 
+        :tickets:
 
       Added an example to the hybrid docs
       of a "transformer" - a hybrid that returns a
@@ -1855,7 +1867,7 @@
 
     .. change::
         :tags: ext, bug
-        :tickets: 
+        :tickets:
 
       the @compiles decorator raises an
       informative error message when no "default"
@@ -1864,7 +1876,7 @@
 
     .. change::
         :tags: examples, bug
-        :tickets: 
+        :tickets:
 
       Fixed bug in history_meta.py example where
       the "unique" flag was not removed from a
@@ -1916,7 +1928,7 @@
 
     .. change::
         :tags: orm
-        :tickets: 
+        :tickets:
 
       added "adapt_on_names" boolean flag to orm.aliased()
       construct.  Allows an aliased() construct
@@ -1927,7 +1939,7 @@
 
     .. change::
         :tags: orm
-        :tickets: 
+        :tickets:
 
       Added new flag expire_on_flush=False to column_property(),
       marks those properties that would otherwise be considered
@@ -1959,7 +1971,7 @@
 
     .. change::
         :tags: orm
-        :tickets: 
+        :tickets:
 
       Fixed a variety of synonym()-related regressions
       from 0.6:
@@ -2013,7 +2025,7 @@
 
     .. change::
         :tags: orm
-        :tickets: 
+        :tickets:
 
       Query will convert an OFFSET of zero when
       slicing into None, so that needless OFFSET
@@ -2021,7 +2033,7 @@
 
     .. change::
         :tags: orm
-        :tickets: 
+        :tickets:
 
       Repaired edge case where mapper would fail
       to fully update internal state when a relationship
@@ -2034,7 +2046,7 @@
 
       Fixed bug whereby if __eq__() was
       redefined, a relationship many-to-one lazyload
-      would hit the __eq__() and fail. 
+      would hit the __eq__() and fail.
       Does not apply to 0.6.9.
 
     .. change::
@@ -2048,7 +2060,7 @@
 
     .. change::
         :tags: orm
-        :tickets: 
+        :tickets:
 
       New event hook, MapperEvents.after_configured().
       Called after a configure() step has completed and
@@ -2183,7 +2195,7 @@
 
     .. change::
         :tags: engine
-        :tickets: 
+        :tickets:
 
       Added optional "sa_pool_key" argument to
       pool.manage(dbapi).connect() so that serialization
@@ -2222,7 +2234,7 @@
 
     .. change::
         :tags: sqlite
-        :tickets: 
+        :tickets:
 
       Ensured that the same ValueError is raised for
       illegal date/time/datetime string parsed from
@@ -2265,7 +2277,7 @@
 
     .. change::
         :tags: postgresql
-        :tickets: 
+        :tickets:
 
       Use an atomic counter as the "random number"
       source for server side cursor names;
@@ -2395,7 +2407,7 @@
 
       Adjusted dictlike-polymorphic.py example
       to apply the CAST such that it works on
-      PG, other databases. 
+      PG, other databases.
       Also in 0.6.9.
 
 .. changelog::
@@ -2450,7 +2462,7 @@
       from a joined-inh structure to itself on
       relationship() with join condition on the child
       table would convert the lead entity into the
-      joined one inappropriately. 
+      joined one inappropriately.
       Also in 0.6.9.
 
     .. change::
@@ -2495,7 +2507,7 @@
       sorting of persistent + pending objects during
       flush would produce an illegal comparison,
       if the persistent object primary key
-      is not a single integer. 
+      is not a single integer.
       Also in 0.6.9
 
     .. change::
@@ -2505,7 +2517,7 @@
       Fixed bug whereby the source clause
       used by query.join() would be inconsistent
       if against a column expression that combined
-      multiple entities together. 
+      multiple entities together.
       Also in 0.6.9
 
     .. change::
@@ -2518,7 +2530,7 @@
       as SQLA should never consult these,
       the methods would be consulted if the class
       was part of a "composite" (i.e. non-single-entity)
-      result set. 
+      result set.
       Also in 0.6.9.
 
     .. change::
@@ -2553,7 +2565,7 @@
 
     .. change::
         :tags: orm
-        :tickets: 
+        :tickets:
 
       Added the same "columns-only" check to
       mapper.polymorphic_on as used when
@@ -2612,7 +2624,7 @@
 
     .. change::
         :tags: schema
-        :tickets: 
+        :tickets:
 
       Added an informative error message when
       ForeignKeyConstraint refers to a column name in
@@ -2630,7 +2642,7 @@
 
     .. change::
         :tags: schema
-        :tickets: 
+        :tickets:
 
       Fixed bug where "autoincrement" detection on
       Table would fail if the type had no "affinity"
@@ -2649,7 +2661,7 @@
 
     .. change::
         :tags: engine
-        :tickets: 
+        :tickets:
 
       Context manager provided by Connection.begin()
       will issue rollback() if the commit() fails,
@@ -2664,7 +2676,7 @@
 
     .. change::
         :tags: engine
-        :tickets: 
+        :tickets:
 
       Added mixin class sqlalchemy.ext.DontWrapMixin.
       User-defined exceptions of this type are never
@@ -2674,7 +2686,7 @@
 
     .. change::
         :tags: engine
-        :tickets: 
+        :tickets:
 
       StatementException wrapping will display the
       original exception class in the message.
@@ -2719,7 +2731,7 @@
 
     .. change::
         :tags: mssql
-        :tickets: 
+        :tickets:
 
       Adjusted the pyodbc dialect such that bound
       values are passed as bytes and not unicode
@@ -2749,7 +2761,7 @@
         :tickets: 2220
 
       repaired the oracle.RAW type which did not
-      generate the correct DDL. 
+      generate the correct DDL.
       Also in 0.6.9.
 
     .. change::
@@ -2760,7 +2772,7 @@
 
     .. change::
         :tags: oracle
-        :tickets: 
+        :tickets:
 
       Fixed bug in the mutable extension whereby
       if the same type were used twice in one
@@ -2769,7 +2781,7 @@
 
     .. change::
         :tags: oracle
-        :tickets: 
+        :tickets:
 
       Fixed bug in the mutable extension whereby
       if None or a non-corresponding type were set,
@@ -2779,7 +2791,7 @@
 
     .. change::
         :tags: examples
-        :tickets: 
+        :tickets:
 
       Repaired the examples/versioning test runner
       to not rely upon SQLAlchemy test libs,
@@ -2789,7 +2801,7 @@
 
     .. change::
         :tags: examples
-        :tickets: 
+        :tickets:
 
       Tweak to examples/versioning to pick the
       correct foreign key in a multi-level
@@ -2797,7 +2809,7 @@
 
     .. change::
         :tags: examples
-        :tickets: 
+        :tickets:
 
       Fixed the attribute shard example to check
       for bind param callable correctly in 0.7
@@ -2859,7 +2871,7 @@
 
     .. change::
         :tags: sql
-        :tickets: 
+        :tickets:
 
       Fixed bug whereby metadata.reflect(bind)
       would close a Connection passed as a
@@ -2867,7 +2879,7 @@
 
     .. change::
         :tags: sql
-        :tickets: 
+        :tickets:
 
       Streamlined the process by which a Select
       determines what's in it's '.c' collection.
@@ -2879,7 +2891,7 @@
 
     .. change::
         :tags: engine
-        :tickets: 
+        :tickets:
 
       Deprecate schema/SQL-oriented methods on
       Connection/Engine that were never well known
@@ -2921,7 +2933,7 @@
 
     .. change::
         :tags: mysql
-        :tickets: 
+        :tickets:
 
       Unit tests pass 100% on MySQL installed
       on windows.
@@ -2947,7 +2959,7 @@
 
     .. change::
         :tags: mysql
-        :tickets: 
+        :tickets:
 
       supports_sane_rowcount will be set to False
       if using MySQLdb and the DBAPI doesn't provide
@@ -2958,8 +2970,8 @@
     :released: Fri May 20 2011
 
     .. change::
-        :tags: 
-        :tickets: 
+        :tags:
+        :tickets:
 
       This section documents those changes from 0.7b4
       to 0.7.0.  For an overview of what's new in
@@ -3007,7 +3019,7 @@
       for joined-inh subclass related to itself,
       or joined-inh subclass related to a subclass
       of that with no cols in the sub-sub class
-      in the join condition. 
+      in the join condition.
       Also in 0.6.8.
 
     .. change::
@@ -3045,7 +3057,7 @@
 
     .. change::
         :tags: orm
-        :tickets: 
+        :tickets:
 
       added Query.with_session() method, switches
       Query to use a different session.
@@ -3088,7 +3100,7 @@
 
     .. change::
         :tags: orm
-        :tickets: 
+        :tickets:
 
       polymorphic_union() renders the columns in their
       original table order, as according to the first
@@ -3102,7 +3114,7 @@
 
       Fixed bug whereby mapper mapped to an anonymous
       alias would fail if logging were used, due to
-      unescaped % sign in the alias name. 
+      unescaped % sign in the alias name.
       Also in 0.6.8.
 
     .. change::
@@ -3118,7 +3130,7 @@
 
     .. change::
         :tags: sql
-        :tickets: 
+        :tickets:
 
       Changed the handling in determination of join
       conditions such that foreign key errors are
@@ -3131,7 +3143,7 @@
 
     .. change::
         :tags: sql
-        :tickets: 
+        :tickets:
 
       Some improvements to error handling inside
       of the execute procedure to ensure auto-close
@@ -3140,7 +3152,7 @@
 
     .. change::
         :tags: sql
-        :tickets: 
+        :tickets:
 
       metadata.reflect() and reflection.Inspector()
       had some reliance on GC to close connections
@@ -3165,7 +3177,7 @@
 
     .. change::
         :tags: postgresql
-        :tickets: 
+        :tickets:
 
       Fixed the psycopg2_version parsing in the
       psycopg2 dialect.
@@ -3198,7 +3210,7 @@
 
     .. change::
         :tags: examples
-        :tickets: 
+        :tickets:
 
       removed the ancient "polymorphic association"
       examples and replaced with an updated set of
@@ -3220,7 +3232,7 @@
 
     .. change::
         :tags: general
-        :tickets: 
+        :tickets:
 
       Changes to the format of CHANGES, this file.
       The format changes have been applied to
@@ -3228,7 +3240,7 @@
 
     .. change::
         :tags: general
-        :tickets: 
+        :tickets:
 
       The "-declarative" changes will now be listed
       directly under the "-orm" section, as these
@@ -3236,7 +3248,7 @@
 
     .. change::
         :tags: general
-        :tickets: 
+        :tickets:
 
       The 0.5 series changes have been moved to
       the file CHANGES_PRE_06 which replaces
@@ -3244,7 +3256,7 @@
 
     .. change::
         :tags: general
-        :tickets: 
+        :tickets:
 
       The changelog for 0.6.7 and subsequent within
       the 0.6 series is now listed only in the
@@ -3279,7 +3291,7 @@
 
     .. change::
         :tags: orm
-        :tickets: 
+        :tickets:
 
       Still more wording adjustments when a query option
       can't find the target entity.  Explain that the
@@ -3294,7 +3306,7 @@
       the back-referenced collection wouldn't
       properly handle add/removes with no net
       change.  Thanks to Richard Murri for the
-      test case + patch. 
+      test case + patch.
       (also in 0.6.7).
 
     .. change::
@@ -3352,7 +3364,7 @@
 
     .. change::
         :tags: sql
-        :tickets: 
+        :tickets:
 
       Restored the "catchall" constructor on the base
       TypeEngine class, with a deprecation warning.
@@ -3375,12 +3387,12 @@
 
       The limit/offset keywords to select() as well
       as the value passed to select.limit()/offset()
-      will be coerced to integer. 
+      will be coerced to integer.
       (also in 0.6.7)
 
     .. change::
         :tags: sql
-        :tickets: 
+        :tickets:
 
       fixed bug where "from" clause gathering from an
       over() clause would be an itertools.chain() and
@@ -3465,7 +3477,7 @@
 
     .. change::
         :tags: pool
-        :tickets: 
+        :tickets:
 
       The "pool.manage" feature doesn't use pickle
       anymore to hash the arguments for each pool.
@@ -3476,12 +3488,12 @@
 
       Fixed bug where reflection of foreign key
       created as "REFERENCES <tablename>" without
-      col name would fail. 
+      col name would fail.
       (also in 0.6.7)
 
     .. change::
         :tags: postgresql
-        :tickets: 
+        :tickets:
 
       Psycopg2 for Python 3 is now supported.
 
@@ -3532,7 +3544,7 @@
 
     .. change::
         :tags: general
-        :tickets: 
+        :tickets:
 
       Lots of fixes to unit tests when run under Pypy
       (courtesy Alex Gaynor).
@@ -3543,11 +3555,11 @@
 
       Changed the underlying approach to query.count().
       query.count() is now in all cases exactly:
-      
+
           query.
               from_self(func.count(literal_column('1'))).
               scalar()
-      
+
       That is, "select count(1) from (<full query>)".
       This produces a subquery in all cases, but
       vastly simplifies all the guessing count()
@@ -3619,7 +3631,7 @@
 
     .. change::
         :tags: sql
-        :tickets: 
+        :tickets:
 
       Added a fully descriptive error message for the
       case where Column is subclassed and _make_proxy()
@@ -3640,7 +3652,7 @@
 
     .. change::
         :tags: sql
-        :tickets: 
+        :tickets:
 
       To help with the "column_reflect" event being used
       with specific Table objects instead of all instances
@@ -3703,7 +3715,7 @@
         :tickets: 2073
 
       Fixed the BIT type to allow a "length" parameter, "varying"
-      parameter.  Reflection also fixed. 
+      parameter.  Reflection also fixed.
       (also in 0.6.7)
 
     .. change::
@@ -3714,7 +3726,7 @@
       typically when using the Inspector interface, to
       use sys.sql_modules instead of the information schema,
       thereby allowing views definitions longer than 4000
-      characters to be fully returned. 
+      characters to be fully returned.
       (also in 0.6.7)
 
     .. change::
@@ -3741,7 +3753,7 @@
 
     .. change::
         :tags: examples
-        :tickets: 
+        :tickets:
 
       Updated the association, association proxy examples
       to use declarative, added a new example
@@ -3753,7 +3765,7 @@
         :tickets: 2090
 
       The Beaker caching example allows a "query_cls" argument
-      to the query_callable() function. 
+      to the query_callable() function.
       (also in 0.6.7)
 
 .. changelog::
@@ -3852,7 +3864,7 @@
 
     .. change::
         :tags: examples
-        :tickets: 
+        :tickets:
 
       Beaker example now takes into account 'limit'
       and 'offset', bind params within embedded
@@ -3864,8 +3876,8 @@
     :released: Sat Feb 12 2011
 
     .. change::
-        :tags: 
-        :tickets: 
+        :tags:
+        :tickets:
 
       Detailed descriptions of each change below are
       described at:
@@ -3892,7 +3904,7 @@
 
     .. change::
         :tags: general
-        :tickets: 
+        :tickets:
 
       The "sqlalchemy.exceptions" alias in sys.modules
       has been removed.   Base SQLA exceptions are
@@ -3921,7 +3933,7 @@
 
     .. change::
         :tags: orm
-        :tickets: 
+        :tickets:
 
       Mutation Event Extension, supercedes "mutable=True"
 
@@ -4029,7 +4041,7 @@
 
     .. change::
         :tags: orm
-        :tickets: 
+        :tickets:
 
       Query.join(), Query.outerjoin(), eagerload(),
       eagerload_all(), others no longer allow lists
@@ -4038,7 +4050,7 @@
 
     .. change::
         :tags: orm
-        :tickets: 
+        :tickets:
 
       ScopedSession.mapper is removed (deprecated since 0.5).
 
@@ -4062,7 +4074,7 @@
 
     .. change::
         :tags: orm
-        :tickets: 
+        :tickets:
 
       The "name" field used in orm.aliased() now renders
       in the resulting SQL statement.
@@ -4106,7 +4118,7 @@
 
     .. change::
         :tags: orm
-        :tickets: 
+        :tickets:
 
       the value of "passive" as passed to
       attributes.get_history() should be one of the
@@ -4126,7 +4138,7 @@
 
       A warning is emitted when a joined-table inheriting mapper
       has no primary keys on the locally mapped table
-      (but has pks on the superclass table). 
+      (but has pks on the superclass table).
       (also in 0.6.7)
 
     .. change::
@@ -4195,7 +4207,7 @@
 
     .. change::
         :tags: sql
-        :tickets: 
+        :tickets:
 
       select.prefix_with() accepts multiple expressions
       (i.e. *expr), 'prefix' keyword argument to select()
@@ -4203,7 +4215,7 @@
 
     .. change::
         :tags: sql
-        :tickets: 
+        :tickets:
 
       Passing a string to the `distinct` keyword argument
       of `select()` for the purpose of emitting special
@@ -4257,7 +4269,7 @@
 
     .. change::
         :tags: sql
-        :tickets: 
+        :tickets:
 
       The Index() construct can be created inline with a Table
       definition, using strings as column names, as an alternative
@@ -4306,7 +4318,7 @@
 
     .. change::
         :tags: sql
-        :tickets: 
+        :tickets:
 
       Bind parameters present in the "columns clause" of a select
       are now auto-labeled like other "anonymous" clauses,
@@ -4315,7 +4327,7 @@
 
     .. change::
         :tags: sql
-        :tickets: 
+        :tickets:
 
       TypeDecorator is present in the "sqlalchemy" import space.
 
@@ -4406,7 +4418,7 @@
       specified, so that the default length, normally '1'
       as per SQL server documentation, is instead
       'unbounded'.  This also occurs for the VARBINARY type..
-      
+
       This behavior makes these types more closely compatible
       with Postgresql's VARCHAR type which is similarly unbounded
       when no length is specified.
@@ -4423,7 +4435,7 @@
         :tickets: 2047
 
       oursql dialect accepts the same "ssl" arguments in
-      create_engine() as that of MySQLdb. 
+      create_engine() as that of MySQLdb.
       (also in 0.6.7)
 
     .. change::
diff --git a/doc/build/changelog/changelog_08.rst b/doc/build/changelog/changelog_08.rst
index 1cad79e116..6bc6bd4ce1 100644
--- a/doc/build/changelog/changelog_08.rst
+++ b/doc/build/changelog/changelog_08.rst
@@ -6,6 +6,53 @@
 .. changelog::
     :version: 0.8.0b2
 
+    .. change::
+        :tags: sql, bug
+        :tickets: 2618
+
+      The :class:`.DECIMAL` type now honors the "precision" and
+      "scale" arguments when rendering DDL.
+
+    .. change::
+        :tags: orm, bug
+        :tickets: 2624
+
+      The :class:`.MutableComposite` type did not allow for the
+      :meth:`.MutableBase.coerce` method to be used, even though
+      the code seemed to indicate this intent, so this now works
+      and a brief example is added.  As a side-effect,
+      the mechanics of this event handler have been changed so that
+      new :class:`.MutableComposite` types no longer add per-type
+      global event handlers.  Also in 0.7.10.
+
+    .. change::
+        :tags: sql, bug
+        :tickets: 2621
+
+      Made an adjustment to the "boolean", (i.e. ``__nonzero__``)
+      evaluation of binary expressions, i.e. ``x1 == x2``, such
+      that the "auto-grouping" applied by :class:`.BinaryExpression`
+      in some cases won't get in the way of this comparison.
+      Previously, an expression like::
+
+        expr1 = mycolumn > 2
+        bool(expr1 == expr1)
+
+      Would evaulate as ``False``, even though this is an identity
+      comparison, because ``mycolumn > 2`` would be "grouped" before
+      being placed into the :class:`.BinaryExpression`, thus changing
+      its identity.   :class:`.BinaryExpression` now keeps track
+      of the "original" objects passed in.
+      Additionally the ``__nonzero__`` method now only returns if
+      the operator is ``==`` or ``!=`` - all others raise ``TypeError``.
+
+    .. change::
+        :tags: firebird, bug
+        :tickets: 2622
+
+      Added missing import for "fdb" to the experimental
+      "firebird+fdb" dialect.
+
     .. change::
         :tags: orm, feature
 
@@ -14,17 +61,22 @@
 
     .. change::
         :tags: orm, bug
-        :ticket: 2614
+        :tickets: 2614
 
-      Added a new exception to detect the case where two
-      subclasses are being loaded using with_polymorphic(),
-      each subclass contains a relationship attribute of the same
-      name, and eager loading is being applied to one or both.
-      This is an ongoing bug which can't be immediately fixed,
-      so since the results are usually wrong in any case it raises an
-      exception for now.   0.7 has the same issue, so an exception
-      raise here probably means the code was returning the wrong
-      data in 0.7.
+      A second overhaul of aliasing/internal pathing mechanics
+      now allows two subclasses to have different relationships
+      of the same name, supported with subquery or joined eager
+      loading on both simultaneously when a full polymorphic
+      load is used.
+
+    .. change::
+        :tags: orm, bug
+        :tickets: 2617
+
+      Fixed bug whereby a multi-hop subqueryload within
+      a particular with_polymorphic load would produce a KeyError.
+      Takes advantage of the same internal pathing overhaul
+      as :ticket:`2614`.
 
     .. change::
         :tags: sql, bug
diff --git a/doc/build/orm/extensions/mutable.rst b/doc/build/orm/extensions/mutable.rst
index 259055980d..ba3e10542d 100644
--- a/doc/build/orm/extensions/mutable.rst
+++ b/doc/build/orm/extensions/mutable.rst
@@ -9,7 +9,7 @@ API Reference
 -------------
 
 .. autoclass:: MutableBase
-    :members: _parents
+    :members: _parents, coerce
 
 .. autoclass:: Mutable
     :show-inheritance:
diff --git a/doc/build/orm/session.rst b/doc/build/orm/session.rst
index d5cc21e82a..3406894dec 100644
--- a/doc/build/orm/session.rst
+++ b/doc/build/orm/session.rst
@@ -1295,6 +1295,7 @@ things like unique constraint exceptions::
             print "Skipped record %s" % record
     session.commit()
 
+.. _session_autocommit:
 
 Autocommit Mode
 ---------------
@@ -1309,16 +1310,21 @@ results have been iterated.   The :meth:`.Session.flush` operation
 still occurs within the scope of a single transaction, though this transaction
 is closed out after the :meth:`.Session.flush` operation completes.
 
-"autocommit" mode should **not be considered for general use**.   While
-very old versions of SQLAlchemy standardized on this mode, the modern
-:class:`.Session` benefits highly from being given a clear point of transaction
-demarcation via :meth:`.Session.rollback` and :meth:`.Session.commit`.
-The autoflush action can safely emit SQL to the database as needed without
-implicitly producing permanent effects, the contents of attributes
-are expired only when a logical series of steps has completed.   If the
-:class:`.Session` were to be used in pure "autocommit" mode without
-an ongoing transaction, these features should be disabled, that is,
-``autoflush=False, expire_on_commit=False``.
+.. warning::
+
+    "autocommit" mode should **not be considered for general use**.
+    If used, it should always be combined with the usage of
+    :meth:`.Session.begin` and :meth:`.Session.commit`, to ensure
+    a transaction demarcation.
+
+    Executing queries outside of a demarcated transaction is a legacy mode
+    of usage, and can in some cases lead to concurrent connection
+    checkouts.
+
+    In the absense of a demarcated transaction, the :class:`.Session`
+    cannot make appropriate decisions as to when autoflush should
+    occur nor when auto-expiration should occur, so these features
+    should be disabled with ``autoflush=False, expire_on_commit=False``.
 
 Modern usage of "autocommit" is for framework integrations that need to control
 specifically when the "begin" state occurs.  A session which is configured with
diff --git a/lib/sqlalchemy/dialects/firebird/__init__.py b/lib/sqlalchemy/dialects/firebird/__init__.py
index 6b2c6878dd..a974f4bdc6 100644
--- a/lib/sqlalchemy/dialects/firebird/__init__.py
+++ b/lib/sqlalchemy/dialects/firebird/__init__.py
@@ -4,7 +4,7 @@
 # This module is part of SQLAlchemy and is released under
 # the MIT License: http://www.opensource.org/licenses/mit-license.php
 
-from sqlalchemy.dialects.firebird import base, kinterbasdb
+from sqlalchemy.dialects.firebird import base, kinterbasdb, fdb
 
 base.dialect = kinterbasdb.dialect
 
diff --git a/lib/sqlalchemy/event.py b/lib/sqlalchemy/event.py
index bf996ae3c5..6453a3987b 100644
--- a/lib/sqlalchemy/event.py
+++ b/lib/sqlalchemy/event.py
@@ -245,6 +245,9 @@ class _DispatchDescriptor(object):
         self._clslevel = util.defaultdict(list)
         self._empty_listeners = {}
 
+    def _contains(self, cls, evt):
+        return evt in self._clslevel[cls]
+
     def insert(self, obj, target, propagate):
         assert isinstance(target, type), \
                 "Class-level Event targets must be classes."
diff --git a/lib/sqlalchemy/ext/mutable.py b/lib/sqlalchemy/ext/mutable.py
index 36d60d6d51..e290a93e28 100644
--- a/lib/sqlalchemy/ext/mutable.py
+++ b/lib/sqlalchemy/ext/mutable.py
@@ -302,6 +302,31 @@ will flag the attribute as "dirty" on the parent object::
     >>> assert v1 in sess.dirty
     True
 
+Coercing Mutable Composites
+---------------------------
+
+The :meth:`.MutableBase.coerce` method is also supported on composite types.
+In the case of :class:`.MutableComposite`, the :meth:`.MutableBase.coerce`
+method is only called for attribute set operations, not load operations.
+Overriding the :meth:`.MutableBase.coerce` method is essentially equivalent
+to using a :func:`.validates` validation routine for all attributes which
+make use of the custom composite type::
+
+    class Point(MutableComposite):
+        # other Point methods
+        # ...
+
+        def coerce(cls, key, value):
+            if isinstance(value, tuple):
+                value = Point(*value)
+            elif not isinstance(value, Point):
+                raise ValueError("tuple or Point expected")
+            return value
+
+.. versionadded:: 0.7.10,0.8.0b2
+    Support for the :meth:`.MutableBase.coerce` method in conjunction with
+    objects of type :class:`.MutableComposite`.
+
 Supporting Pickling
 --------------------
 
@@ -329,7 +354,7 @@ pickling process of the parent's object-relational state so that the
 """
 from ..orm.attributes import flag_modified
 from .. import event, types
-from ..orm import mapper, object_mapper
+from ..orm import mapper, object_mapper, Mapper
 from ..util import memoized_property
 import weakref
 
@@ -354,9 +379,27 @@ class MutableBase(object):
 
     @classmethod
     def coerce(cls, key, value):
-        """Given a value, coerce it into this type.
+        """Given a value, coerce it into the target type.
+
+        Can be overridden by custom subclasses to coerce incoming
+        data into a particular type.
+
+        By default, raises ``ValueError``.
+
+        This method is called in different scenarios depending on if
+        the parent class is of type :class:`.Mutable` or of type
+        :class:`.MutableComposite`.  In the case of the former, it is called
+        for both attribute-set operations as well as during ORM loading
+        operations.  For the latter, it is only called during attribute-set
+        operations; the mechanics of the :func:`.composite` construct
+        handle coercion during load operations.
+
+
+        :param key: string name of the ORM-mapped attribute being set.
+        :param value: the incoming value.
+        :return: the method should return the coerced value, or raise
+         ``ValueError`` if the coercion cannot be completed.
 
-        By default raises ValueError.
         """
         if value is None:
             return None
@@ -523,11 +566,6 @@ class Mutable(MutableBase):
         return sqltype
 
 
-class _MutableCompositeMeta(type):
-    def __init__(cls, classname, bases, dict_):
-        cls._setup_listeners()
-        return type.__init__(cls, classname, bases, dict_)
-
 
 class MutableComposite(MutableBase):
     """Mixin that defines transparent propagation of change
@@ -536,16 +574,7 @@ class MutableComposite(MutableBase):
 
     See the example in :ref:`mutable_composites` for usage information.
 
-    .. warning::
-
-       The listeners established by the :class:`.MutableComposite`
-       class are *global* to all mappers, and are *not* garbage
-       collected.   Only use :class:`.MutableComposite` for types that are
-       permanent to an application, not with ad-hoc types else this will
-       cause unbounded growth in memory usage.
-
     """
-    __metaclass__ = _MutableCompositeMeta
 
     def changed(self):
         """Subclasses should call this method whenever change events occur."""
@@ -558,24 +587,16 @@ class MutableComposite(MutableBase):
                                     prop._attribute_keys):
                 setattr(parent, attr_name, value)
 
-    @classmethod
-    def _setup_listeners(cls):
-        """Associate this wrapper with all future mapped composites
-        of the given type.
-
-        This is a convenience method that calls ``associate_with_attribute``
-        automatically.
-
-        """
-
-        def listen_for_type(mapper, class_):
-            for prop in mapper.iterate_properties:
-                if (hasattr(prop, 'composite_class') and
-                    issubclass(prop.composite_class, cls)):
-                    cls._listen_on_attribute(
-                        getattr(class_, prop.key), False, class_)
-
-        event.listen(mapper, 'mapper_configured', listen_for_type)
+def _setup_composite_listener():
+    def _listen_for_type(mapper, class_):
+        for prop in mapper.iterate_properties:
+            if (hasattr(prop, 'composite_class') and
+                issubclass(prop.composite_class, MutableComposite)):
+                prop.composite_class._listen_on_attribute(
+                    getattr(class_, prop.key), False, class_)
+    if not Mapper.dispatch.mapper_configured._contains(Mapper, _listen_for_type):
+        event.listen(Mapper, 'mapper_configured', _listen_for_type)
+_setup_composite_listener()
 
 
 class MutableDict(Mutable, dict):
diff --git a/lib/sqlalchemy/ext/serializer.py b/lib/sqlalchemy/ext/serializer.py
index 3ed41f48a3..c129b0dcc7 100644
--- a/lib/sqlalchemy/ext/serializer.py
+++ b/lib/sqlalchemy/ext/serializer.py
@@ -54,6 +54,7 @@ needed for:
 from ..orm import class_mapper
 from ..orm.session import Session
 from ..orm.mapper import Mapper
+from ..orm.interfaces import MapperProperty
 from ..orm.attributes import QueryableAttribute
 from .. import Table, Column
 from ..engine import Engine
@@ -90,6 +91,9 @@ def Serializer(*args, **kw):
             id = "attribute:" + key + ":" + b64encode(pickle.dumps(cls))
         elif isinstance(obj, Mapper) and not obj.non_primary:
             id = "mapper:" + b64encode(pickle.dumps(obj.class_))
+        elif isinstance(obj, MapperProperty) and not obj.parent.non_primary:
+            id = "mapperprop:" + b64encode(pickle.dumps(obj.parent.class_)) + \
+                                    ":" + obj.key
         elif isinstance(obj, Table):
             id = "table:" + str(obj)
         elif isinstance(obj, Column) and isinstance(obj.table, Table):
@@ -134,6 +138,10 @@ def Deserializer(file, metadata=None, scoped_session=None, engine=None):
             elif type_ == "mapper":
                 cls = pickle.loads(b64decode(args))
                 return class_mapper(cls)
+            elif type_ == "mapperprop":
+                mapper, keyname = args.split(':')
+                cls = pickle.loads(b64decode(args))
+                return class_mapper(cls).attrs[keyname]
             elif type_ == "table":
                 return metadata.tables[args]
             elif type_ == "column":
diff --git a/lib/sqlalchemy/orm/interfaces.py b/lib/sqlalchemy/orm/interfaces.py
index c91746da0e..55a980b2e7 100644
--- a/lib/sqlalchemy/orm/interfaces.py
+++ b/lib/sqlalchemy/orm/interfaces.py
@@ -219,6 +219,10 @@ class MapperProperty(_MappedAttribute, _InspectionAttr):
 
         return operator(self.comparator, value)
 
+    def __repr__(self):
+        return '<%s at 0x%x; %s>' % (
+            self.__class__.__name__,
+            id(self), self.key)
 
 class PropComparator(operators.ColumnOperators):
     """Defines boolean, comparison, and other operators for
@@ -413,21 +417,18 @@ class StrategizedProperty(MapperProperty):
             return None
 
     def _get_context_strategy(self, context, path):
-        # this is essentially performance inlining.
-        key = ('loaderstrategy', path.reduced_path + (self.key,))
-        cls = None
-        if key in context.attributes:
-            cls = context.attributes[key]
-        else:
+        strategy_cls = path._inlined_get_for(self, context, 'loaderstrategy')
+
+        if not strategy_cls:
             wc_key = self._wildcard_path
             if wc_key and wc_key in context.attributes:
-                cls = context.attributes[wc_key]
+                strategy_cls = context.attributes[wc_key]
 
-        if cls:
+        if strategy_cls:
             try:
-                return self._strategies[cls]
+                return self._strategies[strategy_cls]
             except KeyError:
-                return self.__init_strategy(cls)
+                return self.__init_strategy(strategy_cls)
         return self.strategy
 
     def _get_strategy(self, cls):
@@ -528,10 +529,8 @@ class PropertyOption(MapperOption):
     def _find_entity_prop_comparator(self, query, token, mapper, raiseerr):
         if orm_util._is_aliased_class(mapper):
             searchfor = mapper
-            isa = False
         else:
             searchfor = orm_util._class_to_mapper(mapper)
-            isa = True
         for ent in query._mapper_entities:
             if ent.corresponds_to(searchfor):
                 return ent
@@ -600,7 +599,7 @@ class PropertyOption(MapperOption):
                 # exhaust current_path before
                 # matching tokens to entities
                 if current_path:
-                    if current_path[1] == token:
+                    if current_path[1].key == token:
                         current_path = current_path[2:]
                         continue
                     else:
@@ -634,7 +633,7 @@ class PropertyOption(MapperOption):
                 # matching tokens to entities
                 if current_path:
                     if current_path[0:2] == \
-                            [token._parententity, prop.key]:
+                            [token._parententity, prop]:
                         current_path = current_path[2:]
                         continue
                     else:
@@ -648,6 +647,7 @@ class PropertyOption(MapperOption):
                                             raiseerr)
                     if not entity:
                         return no_result
+
                     path_element = entity.entity_zero
                     mapper = entity.mapper
             else:
@@ -659,7 +659,7 @@ class PropertyOption(MapperOption):
                 raise sa_exc.ArgumentError("Attribute '%s' does not "
                             "link from element '%s'" % (token, path_element))
 
-            path = path[path_element][prop.key]
+            path = path[path_element][prop]
 
             paths.append(path)
 
@@ -670,7 +670,8 @@ class PropertyOption(MapperOption):
                 if not ext_info.is_aliased_class:
                     ac = orm_util.with_polymorphic(
                                 ext_info.mapper.base_mapper,
-                                ext_info.mapper, aliased=True)
+                                ext_info.mapper, aliased=True,
+                                _use_mapper_path=True)
                     ext_info = inspect(ac)
                 path.set(query, "path_with_polymorphic", ext_info)
             else:
diff --git a/lib/sqlalchemy/orm/loading.py b/lib/sqlalchemy/orm/loading.py
index a5d156a1fb..4bd80c3880 100644
--- a/lib/sqlalchemy/orm/loading.py
+++ b/lib/sqlalchemy/orm/loading.py
@@ -271,6 +271,7 @@ def instance_processor(mapper, context, path, adapter,
     new_populators = []
     existing_populators = []
     eager_populators = []
+
     load_path = context.query._current_path + path \
                 if context.query._current_path.path \
                 else path
@@ -504,9 +505,12 @@ def _populators(mapper, context, path, row, adapter,
     delayed_populators = []
     pops = (new_populators, existing_populators, delayed_populators,
                         eager_populators)
+
     for prop in mapper._props.itervalues():
+
         for i, pop in enumerate(prop.create_row_processor(
-                                    context, path,
+                                    context,
+                                    path,
                                     mapper, row, adapter)):
             if pop is not None:
                 pops[i].append((prop.key, pop))
@@ -529,17 +533,10 @@ def _configure_subclass_mapper(mapper, context, path, adapter):
         if sub_mapper is mapper:
             return None
 
-        # replace the tip of the path info with the subclass mapper
-        # being used, that way accurate "load_path" info is available
-        # for options invoked during deferred loads, e.g.
-        # query(Person).options(defer(Engineer.machines, Machine.name)).
-        # for AliasedClass paths, disregard this step (new in 0.8).
         return instance_processor(
                             sub_mapper,
                             context,
-                            path.parent[sub_mapper]
-                                if not path.is_aliased_class
-                                else path,
+                            path,
                             adapter,
                             polymorphic_from=mapper)
     return configure_subclass_mapper
diff --git a/lib/sqlalchemy/orm/mapper.py b/lib/sqlalchemy/orm/mapper.py
index b89163340c..626105b5e1 100644
--- a/lib/sqlalchemy/orm/mapper.py
+++ b/lib/sqlalchemy/orm/mapper.py
@@ -472,7 +472,7 @@ class Mapper(_InspectionAttr):
     dispatch = event.dispatcher(events.MapperEvents)
 
     @util.memoized_property
-    def _sa_path_registry(self):
+    def _path_registry(self):
         return PathRegistry.per_mapper(self)
 
     def _configure_inheritance(self):
@@ -1403,7 +1403,7 @@ class Mapper(_InspectionAttr):
         if _new_mappers:
             configure_mappers()
         if not self.with_polymorphic:
-            return [self]
+            return []
         return self._mappers_from_spec(*self.with_polymorphic)
 
     @_memoized_configured_property
@@ -1458,10 +1458,10 @@ class Mapper(_InspectionAttr):
         return list(self._iterate_polymorphic_properties(
             self._with_polymorphic_mappers))
 
+
     def _iterate_polymorphic_properties(self, mappers=None):
         """Return an iterator of MapperProperty objects which will render into
         a SELECT."""
-
         if mappers is None:
             mappers = self._with_polymorphic_mappers
 
diff --git a/lib/sqlalchemy/orm/query.py b/lib/sqlalchemy/orm/query.py
index ca334e2735..d6847177f0 100644
--- a/lib/sqlalchemy/orm/query.py
+++ b/lib/sqlalchemy/orm/query.py
@@ -157,7 +157,7 @@ class Query(object):
                 ent.setup_entity(*d[entity])
 
     def _mapper_loads_polymorphically_with(self, mapper, adapter):
-        for m2 in mapper._with_polymorphic_mappers:
+        for m2 in mapper._with_polymorphic_mappers or [mapper]:
             self._polymorphic_adapters[m2] = adapter
             for m in m2.iterate_to_root():
                 self._polymorphic_adapters[m.local_table] = adapter
@@ -2744,17 +2744,24 @@ class _MapperEntity(_QueryEntity):
         self._with_polymorphic = ext_info.with_polymorphic_mappers
         self._polymorphic_discriminator = \
                 ext_info.polymorphic_on
+        self.entity_zero = ext_info
         if ext_info.is_aliased_class:
-            self.entity_zero = ext_info.entity
-            self._label_name = self.entity_zero._sa_label_name
+            self._label_name = self.entity_zero.name
         else:
-            self.entity_zero = self.mapper
             self._label_name = self.mapper.class_.__name__
-        self.path = self.entity_zero._sa_path_registry
+        self.path = self.entity_zero._path_registry
 
     def set_with_polymorphic(self, query, cls_or_mappers,
                                 selectable, polymorphic_on):
+        """Receive an update from a call to query.with_polymorphic().
+
+        Note the newer style of using a free standing with_polymporphic()
+        construct doesn't make use of this method.
+
+
+        """
         if self.is_aliased_class:
+            # TODO: invalidrequest ?
             raise NotImplementedError(
                         "Can't use with_polymorphic() against "
                         "an Aliased object"
@@ -2785,13 +2792,18 @@ class _MapperEntity(_QueryEntity):
         return self.entity_zero
 
     def corresponds_to(self, entity):
-        entity_info = inspect(entity)
-        if entity_info.is_aliased_class or self.is_aliased_class:
-            return entity is self.entity_zero \
-                or \
-                entity in self._with_polymorphic
-        else:
-            return entity.common_parent(self.entity_zero)
+        if entity.is_aliased_class:
+            if self.is_aliased_class:
+                if entity._base_alias is self.entity_zero._base_alias:
+                    return True
+            return False
+        elif self.is_aliased_class:
+            if self.entity_zero._use_mapper_path:
+                return entity in self._with_polymorphic
+            else:
+                return entity is self.entity_zero
+
+        return entity.common_parent(self.entity_zero)
 
     def adapt_to_selectable(self, query, sel):
         query._entities.append(self)
@@ -3008,6 +3020,7 @@ class _ColumnEntity(_QueryEntity):
         if self.entity_zero is None:
             return False
         elif _is_aliased_class(entity):
+            # TODO: polymorphic subclasses ?
             return entity is self.entity_zero
         else:
             return not _is_aliased_class(self.entity_zero) and \
diff --git a/lib/sqlalchemy/orm/session.py b/lib/sqlalchemy/orm/session.py
index e4cb908479..16c882a412 100644
--- a/lib/sqlalchemy/orm/session.py
+++ b/lib/sqlalchemy/orm/session.py
@@ -457,22 +457,29 @@ class Session(_SessionClassMethods):
         generate a :class:`.Session`-producing callable with a given
         set of arguments.
 
-        :param autocommit: Defaults to ``False``. When ``True``, the
-          ``Session`` does not keep a persistent transaction running, and
+        :param autocommit:
+
+          .. warning::
+
+             The autocommit flag is **not for general use**, and if it is used,
+             queries should only be invoked within the span of a
+             :meth:`.Session.begin` / :meth:`.Session.commit` pair.   Executing
+             queries outside of a demarcated transaction is a legacy mode
+             of usage, and can in some cases lead to concurrent connection
+             checkouts.
+
+          Defaults to ``False``. When ``True``, the
+          :class:`.Session` does not keep a persistent transaction running, and
           will acquire connections from the engine on an as-needed basis,
           returning them immediately after their use. Flushes will begin and
           commit (or possibly rollback) their own transaction if no
           transaction is present. When using this mode, the
-          `session.begin()` method may be used to begin a transaction
-          explicitly.
+          :meth:`.Session.begin` method is used to explicitly start
+          transactions.
 
-          Leaving it on its default value of ``False`` means that the
-          ``Session`` will acquire a connection and begin a transaction the
-          first time it is used, which it will maintain persistently until
-          ``rollback()``, ``commit()``, or ``close()`` is called. When the
-          transaction is released by any of these methods, the ``Session``
-          is ready for the next usage, which will again acquire and maintain
-          a new connection/transaction.
+          .. seealso::
+
+            :ref:`session_autocommit`
 
         :param autoflush: When ``True``, all query operations will issue a
            ``flush()`` call to this ``Session`` before proceeding. This is a
diff --git a/lib/sqlalchemy/orm/strategies.py b/lib/sqlalchemy/orm/strategies.py
index 586ec4b4e9..05c7ef37bd 100644
--- a/lib/sqlalchemy/orm/strategies.py
+++ b/lib/sqlalchemy/orm/strategies.py
@@ -303,16 +303,6 @@ class AbstractRelationshipLoader(LoaderStrategy):
         self.uselist = self.parent_property.uselist
 
 
-    def _warn_existing_path(self):
-        raise sa_exc.InvalidRequestError(
-            "Eager loading cannot currently function correctly when two or "
-            "more "
-            "same-named attributes associated with multiple polymorphic "
-            "classes "
-            "of the same base are present.   Encountered more than one "
-            r"eager path for attribute '%s' on mapper '%s'." %
-            (self.key, self.parent.base_mapper, ))
-
 
 class NoLoader(AbstractRelationshipLoader):
     """Provide loading behavior for a :class:`.RelationshipProperty`
@@ -564,7 +554,7 @@ class LazyLoader(AbstractRelationshipLoader):
             q = q.autoflush(False)
 
         if state.load_path:
-            q = q._with_current_path(state.load_path[self.key])
+            q = q._with_current_path(state.load_path[self.parent_property])
 
         if state.load_options:
             q = q._conditional_options(*state.load_options)
@@ -694,7 +684,7 @@ class SubqueryLoader(AbstractRelationshipLoader):
         if not context.query._enable_eagerloads:
             return
 
-        path = path[self.key]
+        path = path[self.parent_property]
 
         # build up a path indicating the path from the leftmost
         # entity to the thing we're subquery loading.
@@ -757,22 +747,20 @@ class SubqueryLoader(AbstractRelationshipLoader):
 
         # add new query to attributes to be picked up
         # by create_row_processor
-        existing = path.replace(context, "subquery", q)
-        if existing:
-            self._warn_existing_path()
+        path.set(context, "subquery", q)
 
     def _get_leftmost(self, subq_path):
         subq_path = subq_path.path
         subq_mapper = orm_util._class_to_mapper(subq_path[0])
 
         # determine attributes of the leftmost mapper
-        if self.parent.isa(subq_mapper) and self.key == subq_path[1]:
+        if self.parent.isa(subq_mapper) and self.parent_property is subq_path[1]:
             leftmost_mapper, leftmost_prop = \
                                     self.parent, self.parent_property
         else:
             leftmost_mapper, leftmost_prop = \
                                     subq_mapper, \
-                                    subq_mapper._props[subq_path[1]]
+                                    subq_path[1]
 
         leftmost_cols = leftmost_prop.local_columns
 
@@ -805,23 +793,35 @@ class SubqueryLoader(AbstractRelationshipLoader):
         # the original query now becomes a subquery
         # which we'll join onto.
         embed_q = q.with_labels().subquery()
-        left_alias = orm_util.AliasedClass(leftmost_mapper, embed_q)
+        left_alias = orm_util.AliasedClass(leftmost_mapper, embed_q,
+                            use_mapper_path=True)
         return left_alias
 
     def _prep_for_joins(self, left_alias, subq_path):
-        subq_path = subq_path.path
-
         # figure out what's being joined.  a.k.a. the fun part
-        to_join = [
-                    (subq_path[i], subq_path[i + 1])
-                    for i in xrange(0, len(subq_path), 2)
-                ]
+        to_join = []
+        pairs = list(subq_path.pairs())
+
+        for i, (mapper, prop) in enumerate(pairs):
+            if i > 0:
+                # look at the previous mapper in the chain -
+                # if it is as or more specific than this prop's
+                # mapper, use that instead.
+                # note we have an assumption here that
+                # the non-first element is always going to be a mapper,
+                # not an AliasedClass
+
+                prev_mapper = pairs[i - 1][1].mapper
+                to_append = prev_mapper if prev_mapper.isa(mapper) else mapper
+            else:
+                to_append = mapper
+
+            to_join.append((to_append, prop.key))
 
         # determine the immediate parent class we are joining from,
         # which needs to be aliased.
-
         if len(to_join) > 1:
-            info = inspect(subq_path[-2])
+            info = inspect(to_join[-1][0])
 
         if len(to_join) < 2:
             # in the case of a one level eager load, this is the
@@ -833,11 +833,13 @@ class SubqueryLoader(AbstractRelationshipLoader):
             # in the vast majority of cases, and [ticket:2014]
             # illustrates a case where sub_path[-2] is a subclass
             # of self.parent
-            parent_alias = orm_util.AliasedClass(subq_path[-2])
+            parent_alias = orm_util.AliasedClass(to_join[-1][0],
+                                use_mapper_path=True)
         else:
             # if of_type() were used leading to this relationship,
             # self.parent is more specific than subq_path[-2]
-            parent_alias = orm_util.AliasedClass(self.parent)
+            parent_alias = orm_util.AliasedClass(self.parent,
+                                use_mapper_path=True)
 
         local_cols = self.parent_property.local_columns
 
@@ -916,9 +918,10 @@ class SubqueryLoader(AbstractRelationshipLoader):
                         "population - eager loading cannot be applied." %
                         self)
 
-        path = path[self.key]
+        path = path[self.parent_property]
 
         subq = path.get(context, 'subquery')
+
         if subq is None:
             return None, None, None
 
@@ -1000,7 +1003,7 @@ class JoinedLoader(AbstractRelationshipLoader):
         if not context.query._enable_eagerloads:
             return
 
-        path = path[self.key]
+        path = path[self.parent_property]
 
         with_polymorphic = None
 
@@ -1040,6 +1043,7 @@ class JoinedLoader(AbstractRelationshipLoader):
             with_polymorphic = None
 
         path = path[self.mapper]
+
         for value in self.mapper._iterate_polymorphic_properties(
                                 mappers=with_polymorphic):
             value.setup(
@@ -1079,7 +1083,8 @@ class JoinedLoader(AbstractRelationshipLoader):
         if with_poly_info:
             to_adapt = with_poly_info.entity
         else:
-            to_adapt = orm_util.AliasedClass(self.mapper)
+            to_adapt = orm_util.AliasedClass(self.mapper,
+                                use_mapper_path=True)
         clauses = orm_util.ORMAdapter(
                     to_adapt,
                     equivalents=self.mapper._equivalent_columns,
@@ -1104,9 +1109,8 @@ class JoinedLoader(AbstractRelationshipLoader):
         )
 
         add_to_collection = context.secondary_columns
-        existing = path.replace(context, "eager_row_processor", clauses)
-        if existing:
-            self._warn_existing_path()
+        path.set(context, "eager_row_processor", clauses)
+
         return clauses, adapter, add_to_collection, allow_innerjoin
 
     def _create_eager_join(self, context, entity,
@@ -1154,7 +1158,8 @@ class JoinedLoader(AbstractRelationshipLoader):
                 onclause = getattr(
                                 orm_util.AliasedClass(
                                         self.parent,
-                                        adapter.selectable
+                                        adapter.selectable,
+                                        use_mapper_path=True
                                 ),
                                 self.key, self.parent_property
                             )
@@ -1238,7 +1243,7 @@ class JoinedLoader(AbstractRelationshipLoader):
                         "population - eager loading cannot be applied." %
                         self)
 
-        our_path = path[self.key]
+        our_path = path[self.parent_property]
 
         eager_adapter = self._create_eager_adapter(
                                                 context,
@@ -1391,15 +1396,13 @@ class LoadEagerFromAliasOption(PropertyOption):
     def process_query_property(self, query, paths):
         if self.chained:
             for path in paths[0:-1]:
-                (root_mapper, propname) = path.path[-2:]
-                prop = root_mapper._props[propname]
+                (root_mapper, prop) = path.path[-2:]
                 adapter = query._polymorphic_adapters.get(prop.mapper, None)
                 path.setdefault(query,
                             "user_defined_eager_row_processor",
                             adapter)
 
-        root_mapper, propname = paths[-1].path[-2:]
-        prop = root_mapper._props[propname]
+        root_mapper, prop = paths[-1].path[-2:]
         if self.alias is not None:
             if isinstance(self.alias, basestring):
                 self.alias = prop.target.alias(self.alias)
diff --git a/lib/sqlalchemy/orm/util.py b/lib/sqlalchemy/orm/util.py
index e5e725138c..04838cb64d 100644
--- a/lib/sqlalchemy/orm/util.py
+++ b/lib/sqlalchemy/orm/util.py
@@ -245,6 +245,8 @@ class ORMAdapter(sql_util.ColumnAdapter):
         else:
             return None
 
+def _unreduce_path(path):
+    return PathRegistry.deserialize(path)
 
 class PathRegistry(object):
     """Represent query load paths and registry functions.
@@ -277,19 +279,13 @@ class PathRegistry(object):
             self.path == other.path
 
     def set(self, reg, key, value):
-        reg._attributes[(key, self.reduced_path)] = value
-
-    def replace(self, reg, key, value):
-        path_key = (key, self.reduced_path)
-        existing = reg._attributes.get(path_key, None)
-        reg._attributes[path_key] = value
-        return existing
+        reg._attributes[(key, self.path)] = value
 
     def setdefault(self, reg, key, value):
-        reg._attributes.setdefault((key, self.reduced_path), value)
+        reg._attributes.setdefault((key, self.path), value)
 
     def get(self, reg, key, value=None):
-        key = (key, self.reduced_path)
+        key = (key, self.path)
         if key in reg._attributes:
             return reg._attributes[key]
         else:
@@ -302,17 +298,25 @@ class PathRegistry(object):
     def length(self):
         return len(self.path)
 
+    def pairs(self):
+        path = self.path
+        for i in xrange(0, len(path), 2):
+            yield path[i], path[i + 1]
+
     def contains_mapper(self, mapper):
         return mapper in self.path
 
     def contains(self, reg, key):
-        return (key, self.reduced_path) in reg._attributes
+        return (key, self.path) in reg._attributes
+
+    def __reduce__(self):
+        return _unreduce_path, (self.serialize(), )
 
     def serialize(self):
         path = self.path
         return zip(
             [m.class_ for m in [path[i] for i in range(0, len(path), 2)]],
-            [path[i] for i in range(1, len(path), 2)] + [None]
+            [path[i].key for i in range(1, len(path), 2)] + [None]
         )
 
     @classmethod
@@ -320,7 +324,10 @@ class PathRegistry(object):
         if path is None:
             return None
 
-        p = tuple(chain(*[(class_mapper(mcls), key) for mcls, key in path]))
+        p = tuple(chain(*[(class_mapper(mcls),
+                            class_mapper(mcls).attrs[key]
+                                if key is not None else None)
+                            for mcls, key in path]))
         if p and p[-1] is None:
             p = p[0:-1]
         return cls.coerce(p)
@@ -337,7 +344,7 @@ class PathRegistry(object):
 
     @classmethod
     def token(cls, token):
-        return KeyRegistry(cls.root, token)
+        return TokenRegistry(cls.root, token)
 
     def __add__(self, other):
         return util.reduce(
@@ -354,19 +361,36 @@ class RootRegistry(PathRegistry):
 
     """
     path = ()
-    reduced_path = ()
 
-    def __getitem__(self, mapper):
-        return mapper._sa_path_registry
+    def __getitem__(self, entity):
+        return entity._path_registry
 PathRegistry.root = RootRegistry()
 
-
-class KeyRegistry(PathRegistry):
-    def __init__(self, parent, key):
-        self.key = key
+class TokenRegistry(PathRegistry):
+    def __init__(self, parent, token):
+        self.token = token
         self.parent = parent
-        self.path = parent.path + (key,)
-        self.reduced_path = parent.reduced_path + (key,)
+        self.path = parent.path + (token,)
+
+    def __getitem__(self, entity):
+        raise NotImplementedError()
+
+class PropRegistry(PathRegistry):
+    def __init__(self, parent, prop):
+        # restate this path in terms of the
+        # given MapperProperty's parent.
+        insp = inspection.inspect(parent[-1])
+        if not insp.is_aliased_class or insp._use_mapper_path:
+            parent = parent.parent[prop.parent]
+        elif insp.is_aliased_class and insp.with_polymorphic_mappers:
+            if prop.parent is not insp.mapper and \
+                prop.parent in insp.with_polymorphic_mappers:
+                subclass_entity = parent[-1]._entity_for_mapper(prop.parent)
+                parent = parent.parent[subclass_entity]
+
+        self.prop = prop
+        self.parent = parent
+        self.path = parent.path + (prop,)
 
     def __getitem__(self, entity):
         if isinstance(entity, (int, slice)):
@@ -381,15 +405,11 @@ class EntityRegistry(PathRegistry, dict):
     is_aliased_class = False
 
     def __init__(self, parent, entity):
-        self.key = reduced_key = entity
+        self.key = entity
         self.parent = parent
-        if hasattr(entity, 'base_mapper'):
-            reduced_key = entity.base_mapper
-        else:
-            self.is_aliased_class = True
+        self.is_aliased_class = entity.is_aliased_class
 
         self.path = parent.path + (entity,)
-        self.reduced_path = parent.reduced_path + (reduced_key,)
 
     def __nonzero__(self):
         return True
@@ -400,8 +420,26 @@ class EntityRegistry(PathRegistry, dict):
         else:
             return dict.__getitem__(self, entity)
 
+    def _inlined_get_for(self, prop, context, key):
+        """an inlined version of:
+
+        cls = path[mapperproperty].get(context, key)
+
+        Skips the isinstance() check in __getitem__
+        and the extra method call for get().
+        Used by StrategizedProperty for its
+        very frequent lookup.
+
+        """
+        path = dict.__getitem__(self, prop)
+        path_key = (key, path.path)
+        if path_key in context._attributes:
+            return context._attributes[path_key]
+        else:
+            return None
+
     def __missing__(self, key):
-        self[key] = item = KeyRegistry(self, key)
+        self[key] = item = PropRegistry(self, key)
         return item
 
 
@@ -448,8 +486,11 @@ class AliasedClass(object):
     def __init__(self, cls, alias=None,
                             name=None,
                             adapt_on_names=False,
+                            #  TODO: None for default here?
                             with_polymorphic_mappers=(),
-                            with_polymorphic_discriminator=None):
+                            with_polymorphic_discriminator=None,
+                            base_alias=None,
+                            use_mapper_path=False):
         mapper = _class_to_mapper(cls)
         if alias is None:
             alias = mapper._with_polymorphic_selectable.alias(name=name)
@@ -458,11 +499,19 @@ class AliasedClass(object):
             mapper,
             alias,
             name,
-            with_polymorphic_mappers,
+            with_polymorphic_mappers
+                if with_polymorphic_mappers
+                else mapper.with_polymorphic_mappers,
             with_polymorphic_discriminator
+                if with_polymorphic_discriminator is not None
+                else mapper.polymorphic_on,
+            base_alias,
+            use_mapper_path
         )
+
         self._setup(self._aliased_insp, adapt_on_names)
 
+
     def _setup(self, aliased_insp, adapt_on_names):
         self.__adapt_on_names = adapt_on_names
         mapper = aliased_insp.mapper
@@ -473,18 +522,13 @@ class AliasedClass(object):
                             equivalents=mapper._equivalent_columns,
                             adapt_on_names=self.__adapt_on_names)
         for poly in aliased_insp.with_polymorphic_mappers:
-            setattr(self, poly.class_.__name__,
-                    AliasedClass(poly.class_, alias))
+            if poly is not mapper:
+                setattr(self, poly.class_.__name__,
+                    AliasedClass(poly.class_, alias, base_alias=self,
+                            use_mapper_path=self._aliased_insp._use_mapper_path))
 
-        # used to assign a name to the RowTuple object
-        # returned by Query.
-        self._sa_label_name = aliased_insp.name
         self.__name__ = 'AliasedClass_%s' % self.__target.__name__
 
-    @util.memoized_property
-    def _sa_path_registry(self):
-        return PathRegistry.per_mapper(self)
-
     def __getstate__(self):
         return {
             'mapper': self._aliased_insp.mapper,
@@ -494,7 +538,9 @@ class AliasedClass(object):
             'with_polymorphic_mappers':
                 self._aliased_insp.with_polymorphic_mappers,
             'with_polymorphic_discriminator':
-                self._aliased_insp.polymorphic_on
+                self._aliased_insp.polymorphic_on,
+            'base_alias': self._aliased_insp._base_alias.entity,
+            'use_mapper_path': self._aliased_insp._use_mapper_path
         }
 
     def __setstate__(self, state):
@@ -503,8 +549,10 @@ class AliasedClass(object):
             state['mapper'],
             state['alias'],
             state['name'],
-            state.get('with_polymorphic_mappers'),
-            state.get('with_polymorphic_discriminator')
+            state['with_polymorphic_mappers'],
+            state['with_polymorphic_discriminator'],
+            state['base_alias'],
+            state['use_mapper_path']
         )
         self._setup(self._aliased_insp, state['adapt_on_names'])
 
@@ -521,7 +569,7 @@ class AliasedClass(object):
         queryattr = attributes.QueryableAttribute(
                                 self, key,
                                 impl=existing.impl,
-                                parententity=self,
+                                parententity=self._aliased_insp,
                                 comparator=comparator)
         setattr(self, key, queryattr)
         return queryattr
@@ -558,17 +606,7 @@ class AliasedClass(object):
             id(self), self.__target.__name__)
 
 
-AliasedInsp = util.namedtuple("AliasedInsp", [
-        "entity",
-        "mapper",
-        "selectable",
-        "name",
-        "with_polymorphic_mappers",
-        "polymorphic_on"
-    ])
-
-
-class AliasedInsp(_InspectionAttr, AliasedInsp):
+class AliasedInsp(_InspectionAttr):
     """Provide an inspection interface for an
     :class:`.AliasedClass` object.
 
@@ -604,6 +642,22 @@ class AliasedInsp(_InspectionAttr, AliasedInsp):
 
     """
 
+    def __init__(self, entity, mapper, selectable, name,
+                    with_polymorphic_mappers, polymorphic_on,
+                    _base_alias, _use_mapper_path):
+        self.entity = entity
+        self.mapper = mapper
+        self.selectable = selectable
+        self.name = name
+        self.with_polymorphic_mappers = with_polymorphic_mappers
+        self.polymorphic_on = polymorphic_on
+
+        # a little dance to get serialization to work
+        self._base_alias = _base_alias._aliased_insp if _base_alias \
+                            and _base_alias is not entity else self
+        self._use_mapper_path = _use_mapper_path
+
+
     is_aliased_class = True
     "always returns True"
 
@@ -613,8 +667,29 @@ class AliasedInsp(_InspectionAttr, AliasedInsp):
         :class:`.AliasedInsp`."""
         return self.mapper.class_
 
+    @util.memoized_property
+    def _path_registry(self):
+        if self._use_mapper_path:
+            return self.mapper._path_registry
+        else:
+            return PathRegistry.per_mapper(self)
+
+    def _entity_for_mapper(self, mapper):
+        self_poly = self.with_polymorphic_mappers
+        if mapper in self_poly:
+            return getattr(self.entity, mapper.class_.__name__)._aliased_insp
+        elif mapper.isa(self.mapper):
+            return self
+        else:
+            assert False, "mapper %s doesn't correspond to %s" % (mapper, self)
+
+    def __repr__(self):
+        return '<AliasedInsp at 0x%x; %s>' % (
+            id(self), self.class_.__name__)
+
 
 inspection._inspects(AliasedClass)(lambda target: target._aliased_insp)
+inspection._inspects(AliasedInsp)(lambda target: target)
 
 
 def aliased(element, alias=None, name=None, adapt_on_names=False):
@@ -699,7 +774,7 @@ def aliased(element, alias=None, name=None, adapt_on_names=False):
 
 def with_polymorphic(base, classes, selectable=False,
                         polymorphic_on=None, aliased=False,
-                        innerjoin=False):
+                        innerjoin=False, _use_mapper_path=False):
     """Produce an :class:`.AliasedClass` construct which specifies
     columns for descendant mappers of the given base.
 
@@ -758,7 +833,8 @@ def with_polymorphic(base, classes, selectable=False,
     return AliasedClass(base,
                 selectable,
                 with_polymorphic_mappers=mappers,
-                with_polymorphic_discriminator=polymorphic_on)
+                with_polymorphic_discriminator=polymorphic_on,
+                use_mapper_path=_use_mapper_path)
 
 
 def _orm_annotate(element, exclude=None):
@@ -1109,6 +1185,7 @@ def _entity_descriptor(entity, key):
         description = entity
         entity = insp.c
     elif insp.is_aliased_class:
+        entity = insp.entity
         description = entity
     elif hasattr(insp, "mapper"):
         description = entity = insp.mapper.class_
diff --git a/lib/sqlalchemy/sql/compiler.py b/lib/sqlalchemy/sql/compiler.py
index 102b44a7e3..215ecf7bde 100644
--- a/lib/sqlalchemy/sql/compiler.py
+++ b/lib/sqlalchemy/sql/compiler.py
@@ -2084,7 +2084,15 @@ class GenericTypeCompiler(engine.TypeCompiler):
                         'scale': type_.scale}
 
     def visit_DECIMAL(self, type_):
-        return "DECIMAL"
+        if type_.precision is None:
+            return "DECIMAL"
+        elif type_.scale is None:
+            return "DECIMAL(%(precision)s)" % \
+                        {'precision': type_.precision}
+        else:
+            return "DECIMAL(%(precision)s, %(scale)s)" % \
+                        {'precision': type_.precision,
+                        'scale': type_.scale}
 
     def visit_INTEGER(self, type_):
         return "INTEGER"
diff --git a/lib/sqlalchemy/sql/expression.py b/lib/sqlalchemy/sql/expression.py
index 3dc8dfea49..aa912a0f6d 100644
--- a/lib/sqlalchemy/sql/expression.py
+++ b/lib/sqlalchemy/sql/expression.py
@@ -3723,6 +3723,7 @@ class BinaryExpression(ColumnElement):
         # refer to BinaryExpression directly and pass strings
         if isinstance(operator, basestring):
             operator = operators.custom_op(operator)
+        self._orig = (left, right)
         self.left = _literal_as_text(left).self_group(against=operator)
         self.right = _literal_as_text(right).self_group(against=operator)
         self.operator = operator
@@ -3735,9 +3736,9 @@ class BinaryExpression(ColumnElement):
             self.modifiers = modifiers
 
     def __nonzero__(self):
-        try:
-            return self.operator(hash(self.left), hash(self.right))
-        except:
+        if self.operator in (operator.eq, operator.ne):
+            return self.operator(hash(self._orig[0]), hash(self._orig[1]))
+        else:
             raise TypeError("Boolean value of this clause is not defined")
 
     @property
diff --git a/test/aaa_profiling/test_memusage.py b/test/aaa_profiling/test_memusage.py
index fca0635d24..54c7d7ecc3 100644
--- a/test/aaa_profiling/test_memusage.py
+++ b/test/aaa_profiling/test_memusage.py
@@ -426,12 +426,14 @@ class MemUsageTest(EnsureZeroed):
         metadata = MetaData()
         a = Table("a", metadata,
             Column('id', Integer, primary_key=True),
+            Column('foo', Integer),
+            Column('bar', Integer)
         )
         m1 = mapper(A, a)
         @profile_memory()
         def go():
-            ma = aliased(A)
-            m1._sa_path_registry['foo'][ma]['bar']
+            ma = sa.inspect(aliased(A))
+            m1._path_registry[m1.attrs.foo][ma][m1.attrs.bar]
         go()
         clear_mappers()
 
diff --git a/test/ext/test_mutable.py b/test/ext/test_mutable.py
index 916ff9d4b1..4516e3ac2f 100644
--- a/test/ext/test_mutable.py
+++ b/test/ext/test_mutable.py
@@ -59,35 +59,35 @@ class _MutableDictTestBase(object):
         assert_raises_message(
             ValueError,
             "Attribute 'data' does not accept objects of type",
-            Foo, data=set([1,2,3])
+            Foo, data=set([1, 2, 3])
         )
 
     def test_in_place_mutation(self):
         sess = Session()
 
-        f1 = Foo(data={'a':'b'})
+        f1 = Foo(data={'a': 'b'})
         sess.add(f1)
         sess.commit()
 
         f1.data['a'] = 'c'
         sess.commit()
 
-        eq_(f1.data, {'a':'c'})
+        eq_(f1.data, {'a': 'c'})
 
     def test_replace(self):
         sess = Session()
-        f1 = Foo(data={'a':'b'})
+        f1 = Foo(data={'a': 'b'})
         sess.add(f1)
         sess.flush()
 
-        f1.data = {'b':'c'}
+        f1.data = {'b': 'c'}
         sess.commit()
-        eq_(f1.data, {'b':'c'})
+        eq_(f1.data, {'b': 'c'})
 
     def test_pickle_parent(self):
         sess = Session()
 
-        f1 = Foo(data={'a':'b'})
+        f1 = Foo(data={'a': 'b'})
         sess.add(f1)
         sess.commit()
         f1.data
@@ -102,7 +102,7 @@ class _MutableDictTestBase(object):
 
     def test_unrelated_flush(self):
         sess = Session()
-        f1 = Foo(data={"a":"b"}, unrelated_data="unrelated")
+        f1 = Foo(data={"a": "b"}, unrelated_data="unrelated")
         sess.add(f1)
         sess.flush()
         f1.unrelated_data = "unrelated 2"
@@ -114,14 +114,14 @@ class _MutableDictTestBase(object):
     def _test_non_mutable(self):
         sess = Session()
 
-        f1 = Foo(non_mutable_data={'a':'b'})
+        f1 = Foo(non_mutable_data={'a': 'b'})
         sess.add(f1)
         sess.commit()
 
         f1.non_mutable_data['a'] = 'c'
         sess.commit()
 
-        eq_(f1.non_mutable_data, {'a':'b'})
+        eq_(f1.non_mutable_data, {'a': 'b'})
 
 class MutableWithScalarPickleTest(_MutableDictTestBase, fixtures.MappedTest):
     @classmethod
@@ -142,7 +142,7 @@ class MutableWithScalarPickleTest(_MutableDictTestBase, fixtures.MappedTest):
 
 class MutableWithScalarJSONTest(_MutableDictTestBase, fixtures.MappedTest):
     # json introduced in 2.6
-    __skip_if__ = lambda : sys.version_info < (2, 6),
+    __skip_if__ = lambda: sys.version_info < (2, 6),
 
     @classmethod
     def define_tables(cls, metadata):
@@ -177,7 +177,6 @@ class MutableWithScalarJSONTest(_MutableDictTestBase, fixtures.MappedTest):
 class MutableAssocWithAttrInheritTest(_MutableDictTestBase, fixtures.MappedTest):
     @classmethod
     def define_tables(cls, metadata):
-        MutableDict = cls._type_fixture()
 
         Table('foo', metadata,
             Column('id', Integer, primary_key=True, test_needs_autoincrement=True),
@@ -201,24 +200,24 @@ class MutableAssocWithAttrInheritTest(_MutableDictTestBase, fixtures.MappedTest)
     def test_in_place_mutation(self):
         sess = Session()
 
-        f1 = SubFoo(data={'a':'b'})
+        f1 = SubFoo(data={'a': 'b'})
         sess.add(f1)
         sess.commit()
 
         f1.data['a'] = 'c'
         sess.commit()
 
-        eq_(f1.data, {'a':'c'})
+        eq_(f1.data, {'a': 'c'})
 
     def test_replace(self):
         sess = Session()
-        f1 = SubFoo(data={'a':'b'})
+        f1 = SubFoo(data={'a': 'b'})
         sess.add(f1)
         sess.flush()
 
-        f1.data = {'b':'c'}
+        f1.data = {'b': 'c'}
         sess.commit()
-        eq_(f1.data, {'b':'c'})
+        eq_(f1.data, {'b': 'c'})
 
 class MutableAssociationScalarPickleTest(_MutableDictTestBase, fixtures.MappedTest):
     @classmethod
@@ -235,7 +234,7 @@ class MutableAssociationScalarPickleTest(_MutableDictTestBase, fixtures.MappedTe
 
 class MutableAssociationScalarJSONTest(_MutableDictTestBase, fixtures.MappedTest):
     # json introduced in 2.6
-    __skip_if__ = lambda : sys.version_info < (2, 6),
+    __skip_if__ = lambda: sys.version_info < (2, 6),
 
     @classmethod
     def define_tables(cls, metadata):
@@ -259,7 +258,8 @@ class MutableAssociationScalarJSONTest(_MutableDictTestBase, fixtures.MappedTest
         MutableDict.associate_with(JSONEncodedDict)
 
         Table('foo', metadata,
-            Column('id', Integer, primary_key=True, test_needs_autoincrement=True),
+            Column('id', Integer, primary_key=True,
+                            test_needs_autoincrement=True),
             Column('data', JSONEncodedDict),
             Column('unrelated_data', String(50))
         )
@@ -269,12 +269,19 @@ class _CompositeTestBase(object):
     @classmethod
     def define_tables(cls, metadata):
         Table('foo', metadata,
-            Column('id', Integer, primary_key=True, test_needs_autoincrement=True),
+            Column('id', Integer, primary_key=True,
+                            test_needs_autoincrement=True),
             Column('x', Integer),
             Column('y', Integer),
             Column('unrelated_data', String(50))
         )
 
+    def setup(self):
+        from sqlalchemy.ext import mutable
+        mutable._setup_composite_listener()
+        super(_CompositeTestBase, self).setup()
+
+
     def teardown(self):
         # clear out mapper events
         Mapper.dispatch._clear()
@@ -284,7 +291,6 @@ class _CompositeTestBase(object):
     @classmethod
     def _type_fixture(cls):
 
-        from sqlalchemy.ext.mutable import Mutable
         from sqlalchemy.ext.mutable import MutableComposite
 
         global Point
@@ -322,7 +328,7 @@ class MutableCompositesUnpickleTest(_CompositeTestBase, fixtures.MappedTest):
         cls.Point = cls._type_fixture()
 
         mapper(FooWithEq, foo, properties={
-            'data':composite(cls.Point, foo.c.x, foo.c.y)
+            'data': composite(cls.Point, foo.c.x, foo.c.y)
         })
 
     def test_unpickle_modified_eq(self):
@@ -339,7 +345,7 @@ class MutableCompositesTest(_CompositeTestBase, fixtures.MappedTest):
         Point = cls._type_fixture()
 
         mapper(Foo, foo, properties={
-            'data':composite(Point, foo.c.x, foo.c.y)
+            'data': composite(Point, foo.c.x, foo.c.y)
         })
 
     def test_in_place_mutation(self):
@@ -403,6 +409,71 @@ class MutableCompositesTest(_CompositeTestBase, fixtures.MappedTest):
 
         eq_(f1.data.x, 5)
 
+class MutableCompositeCustomCoerceTest(_CompositeTestBase, fixtures.MappedTest):
+    @classmethod
+    def _type_fixture(cls):
+
+        from sqlalchemy.ext.mutable import MutableComposite
+
+        global Point
+
+        class Point(MutableComposite):
+            def __init__(self, x, y):
+                self.x = x
+                self.y = y
+
+            @classmethod
+            def coerce(cls, key, value):
+                if isinstance(value, tuple):
+                    value = Point(*value)
+                return value
+
+            def __setattr__(self, key, value):
+                object.__setattr__(self, key, value)
+                self.changed()
+
+            def __composite_values__(self):
+                return self.x, self.y
+
+            def __getstate__(self):
+                return self.x, self.y
+
+            def __setstate__(self, state):
+                self.x, self.y = state
+
+            def __eq__(self, other):
+                return isinstance(other, Point) and \
+                    other.x == self.x and \
+                    other.y == self.y
+        return Point
+
+
+    @classmethod
+    def setup_mappers(cls):
+        foo = cls.tables.foo
+
+        Point = cls._type_fixture()
+
+        mapper(Foo, foo, properties={
+            'data': composite(Point, foo.c.x, foo.c.y)
+        })
+
+    def test_custom_coerce(self):
+        f = Foo()
+        f.data = (3, 4)
+        eq_(f.data, Point(3, 4))
+
+    def test_round_trip_ok(self):
+        sess = Session()
+        f = Foo()
+        f.data = (3, 4)
+
+        sess.add(f)
+        sess.commit()
+
+        eq_(f.data, Point(3, 4))
+
+
 class MutableInheritedCompositesTest(_CompositeTestBase, fixtures.MappedTest):
     @classmethod
     def define_tables(cls, metadata):
@@ -423,7 +494,7 @@ class MutableInheritedCompositesTest(_CompositeTestBase, fixtures.MappedTest):
         Point = cls._type_fixture()
 
         mapper(Foo, foo, properties={
-            'data':composite(Point, foo.c.x, foo.c.y)
+            'data': composite(Point, foo.c.x, foo.c.y)
         })
         mapper(SubFoo, subfoo, inherits=Foo)
 
diff --git a/test/orm/inheritance/test_polymorphic_rel.py b/test/orm/inheritance/test_polymorphic_rel.py
index 8bbde972dd..e22848912f 100644
--- a/test/orm/inheritance/test_polymorphic_rel.py
+++ b/test/orm/inheritance/test_polymorphic_rel.py
@@ -496,41 +496,10 @@ class _PolymorphicTestBase(object):
                 .all(),
             expected)
 
-    # TODO: this fails due to the change
-    # in _configure_subclass_mapper.  however we might not
-    # need it anymore.
-    def test_polymorphic_option(self):
-        """
-        Test that polymorphic loading sets state.load_path with its
-        actual mapper on a subclass, and not the superclass mapper.
-
-        This only works for non-aliased mappers.
-        """
-        paths = []
-        class MyOption(interfaces.MapperOption):
-            propagate_to_loaders = True
-            def process_query_conditionally(self, query):
-                paths.append(query._current_path.path)
-
-        sess = create_session()
-        names = ['dilbert', 'pointy haired boss']
-        dilbert, boss = (
-            sess.query(Person)
-                .options(MyOption())
-                .filter(Person.name.in_(names))
-                .order_by(Person.name).all())
-
-        dilbert.machines
-        boss.paperwork
-
-        eq_(paths,
-            [(class_mapper(Engineer), 'machines'),
-            (class_mapper(Boss), 'paperwork')])
 
     def test_subclass_option_pathing(self):
         from sqlalchemy.orm import defer
         sess = create_session()
-        names = ['dilbert', 'pointy haired boss']
         dilbert = sess.query(Person).\
                 options(defer(Engineer.machines, Machine.name)).\
                 filter(Person.name == 'dilbert').first()
@@ -963,7 +932,7 @@ class _PolymorphicTestBase(object):
                 .filter(palias.name.in_(['dilbert', 'wally'])).all(),
             [e1, e2])
 
-    def test_self_referential(self):
+    def test_self_referential_one(self):
         sess = create_session()
         palias = aliased(Person)
         expected = [(m1, e1), (m1, e2), (m1, b1)]
@@ -975,6 +944,11 @@ class _PolymorphicTestBase(object):
                 .order_by(Person.person_id, palias.person_id).all(),
             expected)
 
+    def test_self_referential_two(self):
+        sess = create_session()
+        palias = aliased(Person)
+        expected = [(m1, e1), (m1, e2), (m1, b1)]
+
         eq_(sess.query(Person, palias)
                 .filter(Person.company_id == palias.company_id)
                 .filter(Person.name == 'dogbert')
diff --git a/test/orm/inheritance/test_relationship.py b/test/orm/inheritance/test_relationship.py
index a630e2f3de..509d540efb 100644
--- a/test/orm/inheritance/test_relationship.py
+++ b/test/orm/inheritance/test_relationship.py
@@ -1,6 +1,6 @@
 from sqlalchemy.orm import create_session, relationship, mapper, \
     contains_eager, joinedload, subqueryload, subqueryload_all,\
-    Session, aliased
+    Session, aliased, with_polymorphic
 
 from sqlalchemy import Integer, String, ForeignKey
 from sqlalchemy.engine import default
@@ -717,15 +717,29 @@ class EagerToSubclassTest(fixtures.MappedTest):
 
     def test_subq_through_related(self):
         Parent = self.classes.Parent
-        Sub = self.classes.Sub
+        Base = self.classes.Base
         sess = Session()
+
         def go():
             eq_(sess.query(Parent)
-                    .options(subqueryload_all(Parent.children, Sub.related))
+                    .options(subqueryload_all(Parent.children, Base.related))
                     .order_by(Parent.data).all(),
                 [p1, p2])
         self.assert_sql_count(testing.db, go, 3)
 
+    def test_subq_through_related_aliased(self):
+        Parent = self.classes.Parent
+        Base = self.classes.Base
+        pa = aliased(Parent)
+        sess = Session()
+
+        def go():
+            eq_(sess.query(pa)
+                    .options(subqueryload_all(pa.children, Base.related))
+                    .order_by(pa.data).all(),
+                [p1, p2])
+        self.assert_sql_count(testing.db, go, 3)
+
 class SubClassEagerToSubClassTest(fixtures.MappedTest):
     """Test joinedloads from subclass to subclass mappers"""
 
@@ -876,3 +890,226 @@ class SubClassEagerToSubClassTest(fixtures.MappedTest):
                 [p1, p2])
         self.assert_sql_count(testing.db, go, 2)
 
+class SameNamedPropTwoPolymorphicSubClassesTest(fixtures.MappedTest):
+    """test pathing when two subclasses contain a different property
+    for the same name, and polymorphic loading is used.
+
+    #2614
+
+    """
+    run_setup_classes = 'once'
+    run_setup_mappers = 'once'
+    run_inserts = 'once'
+    run_deletes = None
+
+    @classmethod
+    def define_tables(cls, metadata):
+        Table('a', metadata,
+            Column('id', Integer, primary_key=True,
+                    test_needs_autoincrement=True),
+            Column('type', String(10))
+        )
+        Table('b', metadata,
+            Column('id', Integer, ForeignKey('a.id'), primary_key=True)
+        )
+        Table('btod', metadata,
+            Column('bid', Integer, ForeignKey('b.id'), nullable=False),
+            Column('did', Integer, ForeignKey('d.id'), nullable=False)
+        )
+        Table('c', metadata,
+            Column('id', Integer, ForeignKey('a.id'), primary_key=True)
+        )
+        Table('ctod', metadata,
+            Column('cid', Integer, ForeignKey('c.id'), nullable=False),
+            Column('did', Integer, ForeignKey('d.id'), nullable=False)
+        )
+        Table('d', metadata,
+            Column('id', Integer, primary_key=True,
+                        test_needs_autoincrement=True)
+        )
+
+    @classmethod
+    def setup_classes(cls):
+        class A(cls.Comparable):
+            pass
+        class B(A):
+            pass
+        class C(A):
+            pass
+        class D(cls.Comparable):
+            pass
+
+    @classmethod
+    def setup_mappers(cls):
+        A = cls.classes.A
+        B = cls.classes.B
+        C = cls.classes.C
+        D = cls.classes.D
+
+        mapper(A, cls.tables.a, polymorphic_on=cls.tables.a.c.type)
+        mapper(B, cls.tables.b, inherits=A, polymorphic_identity='b',
+                    properties={
+                        'related': relationship(D, secondary=cls.tables.btod)
+                    })
+        mapper(C, cls.tables.c, inherits=A, polymorphic_identity='c',
+                    properties={
+                        'related': relationship(D, secondary=cls.tables.ctod)
+                    })
+        mapper(D, cls.tables.d)
+
+
+    @classmethod
+    def insert_data(cls):
+        B = cls.classes.B
+        C = cls.classes.C
+        D = cls.classes.D
+
+        session = Session()
+
+        d = D()
+        session.add_all([
+            B(related=[d]),
+            C(related=[d])
+        ])
+        session.commit()
+
+    def test_free_w_poly_subquery(self):
+        A = self.classes.A
+        B = self.classes.B
+        C = self.classes.C
+        D = self.classes.D
+
+        session = Session()
+        d = session.query(D).one()
+        a_poly = with_polymorphic(A, [B, C])
+        def go():
+            for a in session.query(a_poly).\
+                options(
+                        subqueryload(a_poly.B.related),
+                        subqueryload(a_poly.C.related)):
+                eq_(a.related, [d])
+        self.assert_sql_count(testing.db, go, 3)
+
+    def test_fixed_w_poly_subquery(self):
+        A = self.classes.A
+        B = self.classes.B
+        C = self.classes.C
+        D = self.classes.D
+
+        session = Session()
+        d = session.query(D).one()
+        def go():
+            for a in session.query(A).with_polymorphic([B, C]).\
+                options(subqueryload(B.related), subqueryload(C.related)):
+                eq_(a.related, [d])
+        self.assert_sql_count(testing.db, go, 3)
+
+    def test_free_w_poly_joined(self):
+        A = self.classes.A
+        B = self.classes.B
+        C = self.classes.C
+        D = self.classes.D
+
+        session = Session()
+        d = session.query(D).one()
+        a_poly = with_polymorphic(A, [B, C])
+        def go():
+            for a in session.query(a_poly).\
+                options(
+                        joinedload(a_poly.B.related),
+                        joinedload(a_poly.C.related)):
+                eq_(a.related, [d])
+        self.assert_sql_count(testing.db, go, 1)
+
+    def test_fixed_w_poly_joined(self):
+        A = self.classes.A
+        B = self.classes.B
+        C = self.classes.C
+        D = self.classes.D
+
+        session = Session()
+        d = session.query(D).one()
+        def go():
+            for a in session.query(A).with_polymorphic([B, C]).\
+                options(joinedload(B.related), joinedload(C.related)):
+                eq_(a.related, [d])
+        self.assert_sql_count(testing.db, go, 1)
+
+
+class SubClassToSubClassFromParentTest(fixtures.MappedTest):
+    """test #2617
+
+    """
+    run_setup_classes = 'once'
+    run_setup_mappers = 'once'
+    run_inserts = 'once'
+    run_deletes = None
+
+    @classmethod
+    def define_tables(cls, metadata):
+        Table('z', metadata,
+            Column('id', Integer, primary_key=True,
+                        test_needs_autoincrement=True)
+        )
+        Table('a', metadata,
+            Column('id', Integer, primary_key=True,
+                    test_needs_autoincrement=True),
+            Column('type', String(10)),
+            Column('z_id', Integer, ForeignKey('z.id'))
+        )
+        Table('b', metadata,
+            Column('id', Integer, ForeignKey('a.id'), primary_key=True)
+        )
+        Table('d', metadata,
+            Column('id', Integer, ForeignKey('a.id'), primary_key=True),
+            Column('b_id', Integer, ForeignKey('b.id'))
+        )
+
+    @classmethod
+    def setup_classes(cls):
+        class Z(cls.Comparable):
+            pass
+        class A(cls.Comparable):
+            pass
+        class B(A):
+            pass
+        class D(A):
+            pass
+
+    @classmethod
+    def setup_mappers(cls):
+        Z = cls.classes.Z
+        A = cls.classes.A
+        B = cls.classes.B
+        D = cls.classes.D
+
+        mapper(Z, cls.tables.z)
+        mapper(A, cls.tables.a, polymorphic_on=cls.tables.a.c.type,
+                    with_polymorphic='*',
+                    properties={
+                        'zs': relationship(Z, lazy="subquery")
+                    })
+        mapper(B, cls.tables.b, inherits=A, polymorphic_identity='b',
+                    properties={
+                        'related': relationship(D, lazy="subquery",
+                            primaryjoin=cls.tables.d.c.b_id ==
+                                                cls.tables.b.c.id)
+                    })
+        mapper(D, cls.tables.d, inherits=A, polymorphic_identity='d')
+
+
+    @classmethod
+    def insert_data(cls):
+        B = cls.classes.B
+
+        session = Session()
+        session.add(B())
+        session.commit()
+
+    def test_2617(self):
+        A = self.classes.A
+        session = Session()
+        def go():
+            a1 = session.query(A).first()
+            eq_(a1.related, [])
+        self.assert_sql_count(testing.db, go, 3)
diff --git a/test/orm/inheritance/test_single.py b/test/orm/inheritance/test_single.py
index 08a693b92f..de6e55e956 100644
--- a/test/orm/inheritance/test_single.py
+++ b/test/orm/inheritance/test_single.py
@@ -278,7 +278,8 @@ class RelationshipFromSingleTest(testing.AssertsCompiledSQL, fixtures.MappedTest
 
         sess = create_session()
         context = sess.query(Manager).options(subqueryload('stuff'))._compile_context()
-        subq = context.attributes[('subquery', (class_mapper(Employee), 'stuff'))]
+        subq = context.attributes[('subquery',
+                (class_mapper(Manager), class_mapper(Manager).attrs.stuff))]
 
         self.assert_compile(subq,
                             'SELECT employee_stuff.id AS '
diff --git a/test/orm/test_eager_relations.py b/test/orm/test_eager_relations.py
index ae3853e75f..2c59491b17 100644
--- a/test/orm/test_eager_relations.py
+++ b/test/orm/test_eager_relations.py
@@ -311,6 +311,8 @@ class EagerTest(_fixtures.FixtureTest, testing.AssertsCompiledSQL):
         })
         mapper(Keyword, keywords)
 
+
+
         for opt, count in [
             ((
                 joinedload(User.orders, Order.items),
@@ -2662,128 +2664,3 @@ class CyclicalInheritingEagerTestTwo(fixtures.DeclarativeMappedTest,
         assert len(list(session)) == 3
 
 
-
-class WarnFor2614TestBase(object):
-
-    @classmethod
-    def define_tables(cls, metadata):
-        Table('a', metadata,
-            Column('id', Integer, primary_key=True),
-            Column('type', String(50)),
-        )
-        Table('b', metadata,
-            Column('id', Integer, ForeignKey('a.id'), primary_key=True),
-        )
-        Table('c', metadata,
-            Column('id', Integer, ForeignKey('a.id'), primary_key=True),
-        )
-        Table('d', metadata,
-            Column('id', Integer, primary_key=True),
-            Column('bid', Integer, ForeignKey('b.id')),
-            Column('cid', Integer, ForeignKey('c.id')),
-        )
-
-    def _mapping(self, lazy_b=True, lazy_c=True):
-        class A(object):
-            pass
-
-        class B(A):
-            pass
-
-        class C(A):
-            pass
-
-        class D(object):
-            pass
-
-        mapper(A, self.tables.a, polymorphic_on=self.tables.a.c.type)
-        mapper(B, self.tables.b, inherits=A, polymorphic_identity='b',
-                    properties={
-                        'ds': relationship(D, lazy=lazy_b)
-                    })
-        mapper(C, self.tables.c, inherits=A, polymorphic_identity='c',
-                    properties={
-                        'ds': relationship(D, lazy=lazy_c)
-                    })
-        mapper(D, self.tables.d)
-
-
-        return  A, B, C, D
-
-    def _assert_raises(self, fn):
-        assert_raises_message(
-            sa.exc.InvalidRequestError,
-            "Eager loading cannot currently function correctly when two or more "
-            r"same\-named attributes associated with multiple polymorphic classes "
-            "of the same base are present.   Encountered more than one "
-            r"eager path for attribute 'ds' on mapper 'Mapper\|A\|a'.",
-            fn
-        )
-
-    def test_poly_both_eager(self):
-        A, B, C, D = self._mapping(lazy_b=self.eager_name,
-                                    lazy_c=self.eager_name)
-
-        session = Session()
-        self._assert_raises(
-            session.query(A).with_polymorphic('*').all
-        )
-
-    def test_poly_one_eager(self):
-        A, B, C, D = self._mapping(lazy_b=self.eager_name, lazy_c=True)
-
-        session = Session()
-        session.query(A).with_polymorphic('*').all()
-
-    def test_poly_both_option(self):
-        A, B, C, D = self._mapping()
-
-        session = Session()
-        self._assert_raises(
-            session.query(A).with_polymorphic('*').options(
-                        self.eager_option(B.ds), self.eager_option(C.ds)).all
-        )
-
-    def test_poly_one_option_bs(self):
-        A, B, C, D = self._mapping()
-
-        session = Session()
-
-        # sucks, can't even do eager() on just one of them, as B.ds
-        # hits for both
-        self._assert_raises(
-            session.query(A).with_polymorphic('*').\
-                options(self.eager_option(B.ds)).all
-        )
-
-    def test_poly_one_option_cs(self):
-        A, B, C, D = self._mapping()
-
-        session = Session()
-
-        # sucks, can't even do eager() on just one of them, as B.ds
-        # hits for both
-        self._assert_raises(
-            session.query(A).with_polymorphic('*').\
-                options(self.eager_option(C.ds)).all
-        )
-
-    def test_single_poly_one_option_bs(self):
-        A, B, C, D = self._mapping()
-
-        session = Session()
-
-        session.query(A).with_polymorphic(B).\
-            options(self.eager_option(B.ds)).all()
-
-    def test_lazy_True(self):
-        A, B, C, D = self._mapping()
-
-        session = Session()
-        session.query(A).with_polymorphic('*').all()
-
-class WarnFor2614Test(WarnFor2614TestBase, fixtures.MappedTest):
-    eager_name = "joined"
-
-    def eager_option(self, arg):
-        return joinedload(arg)
diff --git a/test/orm/test_inspect.py b/test/orm/test_inspect.py
index fc2d2181fe..fdf675183a 100644
--- a/test/orm/test_inspect.py
+++ b/test/orm/test_inspect.py
@@ -113,7 +113,7 @@ class TestORMInspection(_fixtures.FixtureTest):
     def test_with_polymorphic(self):
         User = self.classes.User
         insp = inspect(User)
-        eq_(insp.with_polymorphic_mappers, [insp])
+        eq_(insp.with_polymorphic_mappers, [])
 
     def test_col_property(self):
         User = self.classes.User
@@ -198,7 +198,7 @@ class TestORMInspection(_fixtures.FixtureTest):
         is_(prop._parentmapper, class_mapper(User))
         is_(prop.mapper, class_mapper(Address))
 
-        is_(prop._parententity, ua)
+        is_(prop._parententity, inspect(ua))
 
     def test_insp_column_prop(self):
         User = self.classes.User
@@ -222,7 +222,7 @@ class TestORMInspection(_fixtures.FixtureTest):
 
         assert not hasattr(prop, "mapper")
 
-        is_(prop._parententity, ua)
+        is_(prop._parententity, inspect(ua))
 
     def test_rel_accessors(self):
         User = self.classes.User
diff --git a/test/orm/test_joins.py b/test/orm/test_joins.py
index 5ef436b0ff..8fd38a680e 100644
--- a/test/orm/test_joins.py
+++ b/test/orm/test_joins.py
@@ -1922,7 +1922,7 @@ class SelfReferentialTest(fixtures.MappedTest, AssertsCompiledSQL):
         )
 
 
-    def test_multiple_explicit_entities(self):
+    def test_multiple_explicit_entities_one(self):
         Node = self.classes.Node
 
         sess = create_session()
@@ -1938,6 +1938,13 @@ class SelfReferentialTest(fixtures.MappedTest, AssertsCompiledSQL):
             (Node(data='n122'), Node(data='n12'), Node(data='n1'))
         )
 
+    def test_multiple_explicit_entities_two(self):
+        Node = self.classes.Node
+
+        sess = create_session()
+
+        parent = aliased(Node)
+        grandparent = aliased(Node)
         eq_(
             sess.query(Node, parent, grandparent).\
                 join(parent, Node.parent).\
@@ -1947,6 +1954,13 @@ class SelfReferentialTest(fixtures.MappedTest, AssertsCompiledSQL):
             (Node(data='n122'), Node(data='n12'), Node(data='n1'))
         )
 
+    def test_multiple_explicit_entities_three(self):
+        Node = self.classes.Node
+
+        sess = create_session()
+
+        parent = aliased(Node)
+        grandparent = aliased(Node)
         # same, change order around
         eq_(
             sess.query(parent, grandparent, Node).\
@@ -1957,6 +1971,13 @@ class SelfReferentialTest(fixtures.MappedTest, AssertsCompiledSQL):
             (Node(data='n12'), Node(data='n1'), Node(data='n122'))
         )
 
+    def test_multiple_explicit_entities_four(self):
+        Node = self.classes.Node
+
+        sess = create_session()
+
+        parent = aliased(Node)
+        grandparent = aliased(Node)
         eq_(
             sess.query(Node, parent, grandparent).\
                 join(parent, Node.parent).\
@@ -1967,6 +1988,13 @@ class SelfReferentialTest(fixtures.MappedTest, AssertsCompiledSQL):
             (Node(data='n122'), Node(data='n12'), Node(data='n1'))
         )
 
+    def test_multiple_explicit_entities_five(self):
+        Node = self.classes.Node
+
+        sess = create_session()
+
+        parent = aliased(Node)
+        grandparent = aliased(Node)
         eq_(
             sess.query(Node, parent, grandparent).\
                 join(parent, Node.parent).\
diff --git a/test/orm/test_mapper.py b/test/orm/test_mapper.py
index 1d7e0228cd..8c5b9cd849 100644
--- a/test/orm/test_mapper.py
+++ b/test/orm/test_mapper.py
@@ -3278,4 +3278,3 @@ class MagicNamesTest(fixtures.MappedTest):
                   reserved: maps.c.state})
 
 
-
diff --git a/test/orm/test_query.py b/test/orm/test_query.py
index 9bf728de22..9aad19579d 100644
--- a/test/orm/test_query.py
+++ b/test/orm/test_query.py
@@ -2,6 +2,7 @@ import operator
 from sqlalchemy import MetaData, null, exists, text, union, literal, \
     literal_column, func, between, Unicode, desc, and_, bindparam, \
     select, distinct, or_, collate
+from sqlalchemy import inspect
 from sqlalchemy import exc as sa_exc, util
 from sqlalchemy.sql import compiler, table, column
 from sqlalchemy.sql import expression
@@ -2309,6 +2310,9 @@ class OptionsTest(QueryTest):
             if i % 2 == 0:
                 if isinstance(item, type):
                     item = class_mapper(item)
+            else:
+                if isinstance(item, basestring):
+                    item = inspect(r[-1]).mapper.attrs[item]
             r.append(item)
         return tuple(r)
 
@@ -2351,7 +2355,8 @@ class OptionsTest(QueryTest):
         q = sess.query(User)
         opt = self._option_fixture('email_address', 'id')
         q = sess.query(Address)._with_current_path(
-                orm_util.PathRegistry.coerce([class_mapper(User), 'addresses'])
+                orm_util.PathRegistry.coerce([inspect(User),
+                        inspect(User).attrs.addresses])
             )
         self._assert_path_result(opt, q, [])
 
@@ -2462,13 +2467,13 @@ class OptionsTest(QueryTest):
         class SubAddr(Address):
             pass
         mapper(SubAddr, inherits=Address, properties={
-            'flub':relationship(Dingaling)
+            'flub': relationship(Dingaling)
         })
 
         q = sess.query(Address)
         opt = self._option_fixture(SubAddr.flub)
 
-        self._assert_path_result(opt, q, [(Address, 'flub')])
+        self._assert_path_result(opt, q, [(SubAddr, 'flub')])
 
     def test_from_subclass_to_subclass_attr(self):
         Dingaling, Address = self.classes.Dingaling, self.classes.Address
@@ -2477,7 +2482,7 @@ class OptionsTest(QueryTest):
         class SubAddr(Address):
             pass
         mapper(SubAddr, inherits=Address, properties={
-            'flub':relationship(Dingaling)
+            'flub': relationship(Dingaling)
         })
 
         q = sess.query(SubAddr)
@@ -2492,13 +2497,14 @@ class OptionsTest(QueryTest):
         class SubAddr(Address):
             pass
         mapper(SubAddr, inherits=Address, properties={
-            'flub':relationship(Dingaling)
+            'flub': relationship(Dingaling)
         })
 
         q = sess.query(Address)
         opt = self._option_fixture(SubAddr.user)
 
-        self._assert_path_result(opt, q, [(Address, 'user')])
+        self._assert_path_result(opt, q,
+                [(Address, inspect(Address).attrs.user)])
 
     def test_of_type(self):
         User, Address = self.classes.User, self.classes.Address
@@ -2511,9 +2517,11 @@ class OptionsTest(QueryTest):
         q = sess.query(User)
         opt = self._option_fixture(User.addresses.of_type(SubAddr), SubAddr.user)
 
+        u_mapper = inspect(User)
+        a_mapper = inspect(Address)
         self._assert_path_result(opt, q, [
-            (User, 'addresses'),
-            (User, 'addresses', SubAddr, 'user')
+            (u_mapper, u_mapper.attrs.addresses),
+            (u_mapper, u_mapper.attrs.addresses, a_mapper, a_mapper.attrs.user)
         ])
 
     def test_of_type_plus_level(self):
@@ -2525,15 +2533,17 @@ class OptionsTest(QueryTest):
         class SubAddr(Address):
             pass
         mapper(SubAddr, inherits=Address, properties={
-            'flub':relationship(Dingaling)
+            'flub': relationship(Dingaling)
         })
 
         q = sess.query(User)
         opt = self._option_fixture(User.addresses.of_type(SubAddr), SubAddr.flub)
 
+        u_mapper = inspect(User)
+        sa_mapper = inspect(SubAddr)
         self._assert_path_result(opt, q, [
-            (User, 'addresses'),
-            (User, 'addresses', SubAddr, 'flub')
+            (u_mapper, u_mapper.attrs.addresses),
+            (u_mapper, u_mapper.attrs.addresses, sa_mapper, sa_mapper.attrs.flub)
         ])
 
     def test_aliased_single(self):
@@ -2543,7 +2553,7 @@ class OptionsTest(QueryTest):
         ualias = aliased(User)
         q = sess.query(ualias)
         opt = self._option_fixture(ualias.addresses)
-        self._assert_path_result(opt, q, [(ualias, 'addresses')])
+        self._assert_path_result(opt, q, [(inspect(ualias), 'addresses')])
 
     def test_with_current_aliased_single(self):
         User, Address = self.classes.User, self.classes.Address
@@ -2554,7 +2564,7 @@ class OptionsTest(QueryTest):
                         self._make_path_registry([Address, 'user'])
                 )
         opt = self._option_fixture(Address.user, ualias.addresses)
-        self._assert_path_result(opt, q, [(ualias, 'addresses')])
+        self._assert_path_result(opt, q, [(inspect(ualias), 'addresses')])
 
     def test_with_current_aliased_single_nonmatching_option(self):
         User, Address = self.classes.User, self.classes.Address
@@ -2828,8 +2838,8 @@ class OptionsNoPropTest(_fixtures.FixtureTest):
                     cls.tables.addresses, cls.classes.Address,
                     cls.tables.orders, cls.classes.Order)
         mapper(User, users, properties={
-            'addresses':relationship(Address),
-            'orders':relationship(Order)
+            'addresses': relationship(Address),
+            'orders': relationship(Order)
         })
         mapper(Address, addresses)
         mapper(Order, orders)
@@ -2839,7 +2849,7 @@ class OptionsNoPropTest(_fixtures.FixtureTest):
                                 cls.classes.Keyword,
                                 cls.classes.Item)
         mapper(Keyword, keywords, properties={
-            "keywords":column_property(keywords.c.name + "some keyword")
+            "keywords": column_property(keywords.c.name + "some keyword")
         })
         mapper(Item, items,
                properties=dict(keywords=relationship(Keyword,
@@ -2850,7 +2860,7 @@ class OptionsNoPropTest(_fixtures.FixtureTest):
 
         q = create_session().query(*entity_list).\
                             options(joinedload(option))
-        key = ('loaderstrategy', (class_mapper(Item), 'keywords'))
+        key = ('loaderstrategy', (inspect(Item), inspect(Item).attrs.keywords))
         assert key in q._attributes
 
     def _assert_eager_with_entity_exception(self, entity_list, options,
@@ -2865,3 +2875,4 @@ class OptionsNoPropTest(_fixtures.FixtureTest):
         assert_raises_message(sa.exc.ArgumentError, message,
                               create_session().query(column).options,
                               joinedload(eager_option))
+
diff --git a/test/orm/test_subquery_relations.py b/test/orm/test_subquery_relations.py
index 000f4abaf8..a4cc830ee6 100644
--- a/test/orm/test_subquery_relations.py
+++ b/test/orm/test_subquery_relations.py
@@ -1226,24 +1226,24 @@ class InheritanceToRelatedTest(fixtures.MappedTest):
     @classmethod
     def fixtures(cls):
         return dict(
-            foo = [
+            foo=[
                 ('id', 'type', 'related_id'),
                 (1, 'bar', 1),
                 (2, 'bar', 2),
                 (3, 'baz', 1),
                 (4, 'baz', 2),
             ],
-            bar = [
+            bar=[
                 ('id', ),
                 (1,),
                 (2,)
             ],
-            baz = [
+            baz=[
                 ('id', ),
                 (3,),
                 (4,)
             ],
-            related = [
+            related=[
                 ('id', ),
                 (1,),
                 (2,)
@@ -1252,7 +1252,7 @@ class InheritanceToRelatedTest(fixtures.MappedTest):
     @classmethod
     def setup_mappers(cls):
         mapper(cls.classes.Foo, cls.tables.foo, properties={
-            'related':relationship(cls.classes.Related)
+            'related': relationship(cls.classes.Related)
         }, polymorphic_on=cls.tables.foo.c.type)
         mapper(cls.classes.Bar, cls.tables.bar, polymorphic_identity='bar',
                     inherits=cls.classes.Foo)
@@ -1260,22 +1260,43 @@ class InheritanceToRelatedTest(fixtures.MappedTest):
                     inherits=cls.classes.Foo)
         mapper(cls.classes.Related, cls.tables.related)
 
-    def test_caches_query_per_base(self):
+    def test_caches_query_per_base_subq(self):
         Foo, Bar, Baz, Related = self.classes.Foo, self.classes.Bar, \
                         self.classes.Baz, self.classes.Related
         s = Session(testing.db)
         def go():
             eq_(
-                s.query(Foo).with_polymorphic([Bar, Baz]).order_by(Foo.id).options(subqueryload(Foo.related)).all(),
+                s.query(Foo).with_polymorphic([Bar, Baz]).\
+                            order_by(Foo.id).\
+                            options(subqueryload(Foo.related)).all(),
                 [
-                    Bar(id=1,related=Related(id=1)),
-                    Bar(id=2,related=Related(id=2)),
-                    Baz(id=3,related=Related(id=1)),
-                    Baz(id=4,related=Related(id=2))
+                    Bar(id=1, related=Related(id=1)),
+                    Bar(id=2, related=Related(id=2)),
+                    Baz(id=3, related=Related(id=1)),
+                    Baz(id=4, related=Related(id=2))
                 ]
             )
         self.assert_sql_count(testing.db, go, 2)
 
+    def test_caches_query_per_base_joined(self):
+        # technically this should be in test_eager_relations
+        Foo, Bar, Baz, Related = self.classes.Foo, self.classes.Bar, \
+                        self.classes.Baz, self.classes.Related
+        s = Session(testing.db)
+        def go():
+            eq_(
+                s.query(Foo).with_polymorphic([Bar, Baz]).\
+                            order_by(Foo.id).\
+                            options(joinedload(Foo.related)).all(),
+                [
+                    Bar(id=1, related=Related(id=1)),
+                    Bar(id=2, related=Related(id=2)),
+                    Baz(id=3, related=Related(id=1)),
+                    Baz(id=4, related=Related(id=2))
+                ]
+            )
+        self.assert_sql_count(testing.db, go, 1)
+
 class CyclicalInheritingEagerTestOne(fixtures.MappedTest):
 
     @classmethod
@@ -1344,14 +1365,13 @@ class CyclicalInheritingEagerTestTwo(fixtures.DeclarativeMappedTest,
 
     def test_from_subclass(self):
         Director = self.classes.Director
-        PersistentObject = self.classes.PersistentObject
-
 
         s = create_session()
 
         ctx = s.query(Director).options(subqueryload('*'))._compile_context()
 
-        q = ctx.attributes[('subquery', (inspect(PersistentObject), 'movies'))]
+        q = ctx.attributes[('subquery',
+                        (inspect(Director), inspect(Director).attrs.movies))]
         self.assert_compile(q,
             "SELECT anon_1.movie_id AS anon_1_movie_id, "
             "anon_1.persistent_id AS anon_1_persistent_id, "
@@ -1384,10 +1404,3 @@ class CyclicalInheritingEagerTestTwo(fixtures.DeclarativeMappedTest,
         d = session.query(Director).options(subqueryload('*')).first()
         assert len(list(session)) == 3
 
-from . import test_eager_relations
-
-class WarnFor2614Test(test_eager_relations.WarnFor2614TestBase, fixtures.MappedTest):
-    eager_name = "subquery"
-
-    def eager_option(self, arg):
-        return subqueryload(arg)
diff --git a/test/orm/test_utils.py b/test/orm/test_utils.py
index afe8fb5c1f..b2853a8b83 100644
--- a/test/orm/test_utils.py
+++ b/test/orm/test_utils.py
@@ -4,7 +4,7 @@ from sqlalchemy import Column
 from sqlalchemy import Integer
 from sqlalchemy import MetaData
 from sqlalchemy import Table
-from sqlalchemy.orm import aliased
+from sqlalchemy.orm import aliased, with_polymorphic
 from sqlalchemy.orm import mapper, create_session
 from sqlalchemy.testing import fixtures
 from test.orm import _fixtures
@@ -228,6 +228,7 @@ class IdentityKeyTest(_fixtures.FixtureTest):
         key = util.identity_key(User, row=row)
         eq_(key, (User, (1,)))
 
+
 class PathRegistryTest(_fixtures.FixtureTest):
     run_setup_mappers = 'once'
     run_inserts = None
@@ -242,7 +243,7 @@ class PathRegistryTest(_fixtures.FixtureTest):
         umapper = inspect(self.classes.User)
         is_(
             util.RootRegistry()[umapper],
-            umapper._sa_path_registry
+            umapper._path_registry
         )
         eq_(
             util.RootRegistry()[umapper],
@@ -255,9 +256,10 @@ class PathRegistryTest(_fixtures.FixtureTest):
         path = PathRegistry.coerce((umapper,))
 
         eq_(
-            path['addresses'][amapper]['email_address'],
-            PathRegistry.coerce((umapper, 'addresses',
-                                amapper, 'email_address'))
+            path[umapper.attrs.addresses][amapper]
+                [amapper.attrs.email_address],
+            PathRegistry.coerce((umapper, umapper.attrs.addresses,
+                                amapper, amapper.attrs.email_address))
         )
 
     def test_entity_boolean(self):
@@ -267,47 +269,48 @@ class PathRegistryTest(_fixtures.FixtureTest):
 
     def test_key_boolean(self):
         umapper = inspect(self.classes.User)
-        path = PathRegistry.coerce((umapper, 'addresses'))
+        path = PathRegistry.coerce((umapper, umapper.attrs.addresses))
         is_(bool(path), True)
 
     def test_aliased_class(self):
         User = self.classes.User
         ua = aliased(User)
-        path = PathRegistry.coerce((ua, 'addresses'))
+        ua_insp = inspect(ua)
+        path = PathRegistry.coerce((ua_insp, ua_insp.mapper.attrs.addresses))
         assert path.parent.is_aliased_class
 
     def test_indexed_entity(self):
         umapper = inspect(self.classes.User)
         amapper = inspect(self.classes.Address)
-        path = PathRegistry.coerce((umapper, 'addresses',
-                                amapper, 'email_address'))
+        path = PathRegistry.coerce((umapper, umapper.attrs.addresses,
+                                amapper, amapper.attrs.email_address))
         is_(path[0], umapper)
         is_(path[2], amapper)
 
     def test_indexed_key(self):
         umapper = inspect(self.classes.User)
         amapper = inspect(self.classes.Address)
-        path = PathRegistry.coerce((umapper, 'addresses',
-                                amapper, 'email_address'))
-        eq_(path[1], 'addresses')
-        eq_(path[3], 'email_address')
+        path = PathRegistry.coerce((umapper, umapper.attrs.addresses,
+                                amapper, amapper.attrs.email_address))
+        eq_(path[1], umapper.attrs.addresses)
+        eq_(path[3], amapper.attrs.email_address)
 
     def test_slice(self):
         umapper = inspect(self.classes.User)
         amapper = inspect(self.classes.Address)
-        path = PathRegistry.coerce((umapper, 'addresses',
-                                amapper, 'email_address'))
-        eq_(path[1:3], ('addresses', amapper))
+        path = PathRegistry.coerce((umapper, umapper.attrs.addresses,
+                                amapper, amapper.attrs.email_address))
+        eq_(path[1:3], (umapper.attrs.addresses, amapper))
 
     def test_addition(self):
         umapper = inspect(self.classes.User)
         amapper = inspect(self.classes.Address)
-        p1 = PathRegistry.coerce((umapper, 'addresses'))
-        p2 = PathRegistry.coerce((amapper, 'email_address'))
+        p1 = PathRegistry.coerce((umapper, umapper.attrs.addresses))
+        p2 = PathRegistry.coerce((amapper, amapper.attrs.email_address))
         eq_(
             p1 + p2,
-            PathRegistry.coerce((umapper, 'addresses',
-                                amapper, 'email_address'))
+            PathRegistry.coerce((umapper, umapper.attrs.addresses,
+                                amapper, amapper.attrs.email_address))
         )
 
     def test_length(self):
@@ -315,10 +318,10 @@ class PathRegistryTest(_fixtures.FixtureTest):
         amapper = inspect(self.classes.Address)
         pneg1 = PathRegistry.coerce(())
         p0 = PathRegistry.coerce((umapper,))
-        p1 = PathRegistry.coerce((umapper, 'addresses'))
-        p2 = PathRegistry.coerce((umapper, 'addresses', amapper))
-        p3 = PathRegistry.coerce((umapper, 'addresses',
-                                amapper, 'email_address'))
+        p1 = PathRegistry.coerce((umapper, umapper.attrs.addresses))
+        p2 = PathRegistry.coerce((umapper, umapper.attrs.addresses, amapper))
+        p3 = PathRegistry.coerce((umapper, umapper.attrs.addresses,
+                                amapper, amapper.attrs.email_address))
 
         eq_(len(pneg1), 0)
         eq_(len(p0), 1)
@@ -334,14 +337,17 @@ class PathRegistryTest(_fixtures.FixtureTest):
     def test_eq(self):
         umapper = inspect(self.classes.User)
         amapper = inspect(self.classes.Address)
-        p1 = PathRegistry.coerce((umapper, 'addresses'))
-        p2 = PathRegistry.coerce((umapper, 'addresses'))
-        p3 = PathRegistry.coerce((umapper, 'other'))
-        p4 = PathRegistry.coerce((amapper, 'addresses'))
-        p5 = PathRegistry.coerce((umapper, 'addresses', amapper))
-        p6 = PathRegistry.coerce((amapper, 'user', umapper, 'addresses'))
-        p7 = PathRegistry.coerce((amapper, 'user', umapper, 'addresses',
-                                amapper, 'email_address'))
+        u_alias = inspect(aliased(self.classes.User))
+        p1 = PathRegistry.coerce((umapper, umapper.attrs.addresses))
+        p2 = PathRegistry.coerce((umapper, umapper.attrs.addresses))
+        p3 = PathRegistry.coerce((umapper, umapper.attrs.name))
+        p4 = PathRegistry.coerce((u_alias, umapper.attrs.addresses))
+        p5 = PathRegistry.coerce((umapper, umapper.attrs.addresses, amapper))
+        p6 = PathRegistry.coerce((amapper, amapper.attrs.user, umapper,
+                                umapper.attrs.addresses))
+        p7 = PathRegistry.coerce((amapper, amapper.attrs.user, umapper,
+                                umapper.attrs.addresses,
+                                amapper, amapper.attrs.email_address))
 
         is_(p1 == p2, True)
         is_(p1 == p3, False)
@@ -358,7 +364,7 @@ class PathRegistryTest(_fixtures.FixtureTest):
     def test_contains_mapper(self):
         umapper = inspect(self.classes.User)
         amapper = inspect(self.classes.Address)
-        p1 = PathRegistry.coerce((umapper, 'addresses'))
+        p1 = PathRegistry.coerce((umapper, umapper.attrs.addresses))
         assert p1.contains_mapper(umapper)
         assert not p1.contains_mapper(amapper)
 
@@ -373,18 +379,18 @@ class PathRegistryTest(_fixtures.FixtureTest):
         umapper = inspect(self.classes.User)
         amapper = inspect(self.classes.Address)
 
-        p1 = PathRegistry.coerce((umapper, 'addresses'))
-        p2 = PathRegistry.coerce((umapper, 'addresses', amapper))
-        p3 = PathRegistry.coerce((amapper, 'email_address'))
+        p1 = PathRegistry.coerce((umapper, umapper.attrs.addresses))
+        p2 = PathRegistry.coerce((umapper, umapper.attrs.addresses, amapper))
+        p3 = PathRegistry.coerce((amapper, amapper.attrs.email_address))
 
         eq_(
-            p1.path, (umapper, 'addresses')
+            p1.path, (umapper, umapper.attrs.addresses)
         )
         eq_(
-            p2.path, (umapper, 'addresses', amapper)
+            p2.path, (umapper, umapper.attrs.addresses, amapper)
         )
         eq_(
-            p3.path, (amapper, 'email_address')
+            p3.path, (amapper, amapper.attrs.email_address)
         )
 
     def test_registry_set(self):
@@ -392,9 +398,9 @@ class PathRegistryTest(_fixtures.FixtureTest):
         umapper = inspect(self.classes.User)
         amapper = inspect(self.classes.Address)
 
-        p1 = PathRegistry.coerce((umapper, 'addresses'))
-        p2 = PathRegistry.coerce((umapper, 'addresses', amapper))
-        p3 = PathRegistry.coerce((amapper, 'email_address'))
+        p1 = PathRegistry.coerce((umapper, umapper.attrs.addresses))
+        p2 = PathRegistry.coerce((umapper, umapper.attrs.addresses, amapper))
+        p3 = PathRegistry.coerce((amapper, amapper.attrs.email_address))
 
         p1.set(reg, "p1key", "p1value")
         p2.set(reg, "p2key", "p2value")
@@ -413,9 +419,9 @@ class PathRegistryTest(_fixtures.FixtureTest):
         umapper = inspect(self.classes.User)
         amapper = inspect(self.classes.Address)
 
-        p1 = PathRegistry.coerce((umapper, 'addresses'))
-        p2 = PathRegistry.coerce((umapper, 'addresses', amapper))
-        p3 = PathRegistry.coerce((amapper, 'email_address'))
+        p1 = PathRegistry.coerce((umapper, umapper.attrs.addresses))
+        p2 = PathRegistry.coerce((umapper, umapper.attrs.addresses, amapper))
+        p3 = PathRegistry.coerce((amapper, amapper.attrs.email_address))
         reg.update(
             {
                 ('p1key', p1.path): 'p1value',
@@ -435,9 +441,9 @@ class PathRegistryTest(_fixtures.FixtureTest):
         umapper = inspect(self.classes.User)
         amapper = inspect(self.classes.Address)
 
-        p1 = PathRegistry.coerce((umapper, 'addresses'))
-        p2 = PathRegistry.coerce((umapper, 'addresses', amapper))
-        p3 = PathRegistry.coerce((amapper, 'email_address'))
+        p1 = PathRegistry.coerce((umapper, umapper.attrs.addresses))
+        p2 = PathRegistry.coerce((umapper, umapper.attrs.addresses, amapper))
+        p3 = PathRegistry.coerce((amapper, amapper.attrs.email_address))
         reg.update(
             {
                 ('p1key', p1.path): 'p1value',
@@ -455,8 +461,8 @@ class PathRegistryTest(_fixtures.FixtureTest):
         umapper = inspect(self.classes.User)
         amapper = inspect(self.classes.Address)
 
-        p1 = PathRegistry.coerce((umapper, 'addresses'))
-        p2 = PathRegistry.coerce((umapper, 'addresses', amapper))
+        p1 = PathRegistry.coerce((umapper, umapper.attrs.addresses))
+        p2 = PathRegistry.coerce((umapper, umapper.attrs.addresses, amapper))
         reg.update(
             {
                 ('p1key', p1.path): 'p1value',
@@ -481,10 +487,10 @@ class PathRegistryTest(_fixtures.FixtureTest):
         umapper = inspect(self.classes.User)
         amapper = inspect(self.classes.Address)
 
-        p1 = PathRegistry.coerce((umapper, 'addresses', amapper,
-                            'email_address'))
-        p2 = PathRegistry.coerce((umapper, 'addresses', amapper))
-        p3 = PathRegistry.coerce((umapper, 'addresses'))
+        p1 = PathRegistry.coerce((umapper, umapper.attrs.addresses, amapper,
+                            amapper.attrs.email_address))
+        p2 = PathRegistry.coerce((umapper, umapper.attrs.addresses, amapper))
+        p3 = PathRegistry.coerce((umapper, umapper.attrs.addresses))
         eq_(
             p1.serialize(),
             [(User, "addresses"), (Address, "email_address")]
@@ -505,10 +511,10 @@ class PathRegistryTest(_fixtures.FixtureTest):
         amapper = inspect(self.classes.Address)
 
 
-        p1 = PathRegistry.coerce((umapper, 'addresses', amapper,
-                            'email_address'))
-        p2 = PathRegistry.coerce((umapper, 'addresses', amapper))
-        p3 = PathRegistry.coerce((umapper, 'addresses'))
+        p1 = PathRegistry.coerce((umapper, umapper.attrs.addresses, amapper,
+                            amapper.attrs.email_address))
+        p2 = PathRegistry.coerce((umapper, umapper.attrs.addresses, amapper))
+        p3 = PathRegistry.coerce((umapper, umapper.attrs.addresses))
 
         eq_(
             PathRegistry.deserialize([(User, "addresses"),
@@ -523,3 +529,135 @@ class PathRegistryTest(_fixtures.FixtureTest):
             PathRegistry.deserialize([(User, "addresses")]),
             p3
         )
+
+from .inheritance import _poly_fixtures
+class PathRegistryInhTest(_poly_fixtures._Polymorphic):
+    run_setup_mappers = 'once'
+    run_inserts = None
+    run_deletes = None
+
+    def test_plain(self):
+        Person = _poly_fixtures.Person
+        Engineer = _poly_fixtures.Engineer
+        pmapper = inspect(Person)
+        emapper = inspect(Engineer)
+
+        p1 = PathRegistry.coerce((pmapper, emapper.attrs.machines))
+
+        # given a mapper and an attribute on a subclass,
+        # the path converts what you get to be against that subclass
+        eq_(
+            p1.path,
+            (emapper, emapper.attrs.machines)
+        )
+
+    def test_plain_compound(self):
+        Company = _poly_fixtures.Company
+        Person = _poly_fixtures.Person
+        Engineer = _poly_fixtures.Engineer
+        cmapper = inspect(Company)
+        pmapper = inspect(Person)
+        emapper = inspect(Engineer)
+
+        p1 = PathRegistry.coerce((cmapper, cmapper.attrs.employees,
+                        pmapper, emapper.attrs.machines))
+
+        # given a mapper and an attribute on a subclass,
+        # the path converts what you get to be against that subclass
+        eq_(
+            p1.path,
+            (cmapper, cmapper.attrs.employees, emapper, emapper.attrs.machines)
+        )
+
+    def test_plain_aliased(self):
+        Person = _poly_fixtures.Person
+        Engineer = _poly_fixtures.Engineer
+        emapper = inspect(Engineer)
+
+        p_alias = aliased(Person)
+        p_alias = inspect(p_alias)
+
+        p1 = PathRegistry.coerce((p_alias, emapper.attrs.machines))
+        # plain AliasedClass - the path keeps that AliasedClass directly
+        # as is in the path
+        eq_(
+            p1.path,
+            (p_alias, emapper.attrs.machines)
+        )
+
+    def test_plain_aliased_compound(self):
+        Company = _poly_fixtures.Company
+        Person = _poly_fixtures.Person
+        Engineer = _poly_fixtures.Engineer
+        cmapper = inspect(Company)
+        emapper = inspect(Engineer)
+
+        c_alias = aliased(Company)
+        p_alias = aliased(Person)
+
+        c_alias = inspect(c_alias)
+        p_alias = inspect(p_alias)
+
+        p1 = PathRegistry.coerce((c_alias, cmapper.attrs.employees,
+                    p_alias, emapper.attrs.machines))
+        # plain AliasedClass - the path keeps that AliasedClass directly
+        # as is in the path
+        eq_(
+            p1.path,
+            (c_alias, cmapper.attrs.employees, p_alias, emapper.attrs.machines)
+        )
+
+    def test_with_poly_sub(self):
+        Person = _poly_fixtures.Person
+        Engineer = _poly_fixtures.Engineer
+        emapper = inspect(Engineer)
+
+        p_poly = with_polymorphic(Person, [Engineer])
+        e_poly = inspect(p_poly.Engineer)
+        p_poly = inspect(p_poly)
+
+        p1 = PathRegistry.coerce((p_poly, emapper.attrs.machines))
+
+        # polymorphic AliasedClass - the path uses _entity_for_mapper()
+        # to get the most specific sub-entity
+        eq_(
+            p1.path,
+            (e_poly, emapper.attrs.machines)
+        )
+
+    def test_with_poly_base(self):
+        Person = _poly_fixtures.Person
+        Engineer = _poly_fixtures.Engineer
+        pmapper = inspect(Person)
+        emapper = inspect(Engineer)
+
+        p_poly = with_polymorphic(Person, [Engineer])
+        p_poly = inspect(p_poly)
+
+        # "name" is actually on Person, not Engineer
+        p1 = PathRegistry.coerce((p_poly, emapper.attrs.name))
+
+        # polymorphic AliasedClass - because "name" is on Person,
+        # we get Person, not Engineer
+        eq_(
+            p1.path,
+            (p_poly, pmapper.attrs.name)
+        )
+
+    def test_with_poly_use_mapper(self):
+        Person = _poly_fixtures.Person
+        Engineer = _poly_fixtures.Engineer
+        emapper = inspect(Engineer)
+
+        p_poly = with_polymorphic(Person, [Engineer], _use_mapper_path=True)
+        p_poly = inspect(p_poly)
+
+        p1 = PathRegistry.coerce((p_poly, emapper.attrs.machines))
+
+        # polymorphic AliasedClass with the "use_mapper_path" flag -
+        # the AliasedClass acts just like the base mapper
+        eq_(
+            p1.path,
+            (emapper, emapper.attrs.machines)
+        )
+
diff --git a/test/sql/test_operators.py b/test/sql/test_operators.py
index 9da9d94c32..45f4978ed1 100644
--- a/test/sql/test_operators.py
+++ b/test/sql/test_operators.py
@@ -833,6 +833,58 @@ class ComparisonOperatorTest(fixtures.TestBase, testing.AssertsCompiledSQL):
     def test_comparison_operators_ge(self):
         self._test_comparison_op(operator.ge, '>=', '<=')
 
+class NonZeroTest(fixtures.TestBase):
+    def _raises(self, expr):
+        assert_raises_message(
+            TypeError,
+            "Boolean value of this clause is not defined",
+            bool, expr
+        )
+
+    def _assert_true(self, expr):
+        is_(bool(expr), True)
+
+    def _assert_false(self, expr):
+        is_(bool(expr), False)
+
+    def test_column_identity_eq(self):
+        c1 = column('c1')
+        self._assert_true(c1 == c1)
+
+    def test_column_identity_gt(self):
+        c1 = column('c1')
+        self._raises(c1 > c1)
+
+    def test_column_compare_eq(self):
+        c1, c2 = column('c1'), column('c2')
+        self._assert_false(c1 == c2)
+
+    def test_column_compare_gt(self):
+        c1, c2 = column('c1'), column('c2')
+        self._raises(c1 > c2)
+
+    def test_binary_identity_eq(self):
+        c1 = column('c1')
+        expr = c1 > 5
+        self._assert_true(expr == expr)
+
+    def test_labeled_binary_identity_eq(self):
+        c1 = column('c1')
+        expr = (c1 > 5).label(None)
+        self._assert_true(expr == expr)
+
+    def test_annotated_binary_identity_eq(self):
+        c1 = column('c1')
+        expr1 = (c1 > 5)
+        expr2 = expr1._annotate({"foo": "bar"})
+        self._assert_true(expr1 == expr2)
+
+    def test_labeled_binary_compare_gt(self):
+        c1 = column('c1')
+        expr1 = (c1 > 5).label(None)
+        expr2 = (c1 > 5).label(None)
+        self._assert_false(expr1 == expr2)
+
 class NegationTest(fixtures.TestBase, testing.AssertsCompiledSQL):
     __dialect__ = 'default'
 
diff --git a/test/sql/test_selectable.py b/test/sql/test_selectable.py
index 65dc654702..a60916b44a 100644
--- a/test/sql/test_selectable.py
+++ b/test/sql/test_selectable.py
@@ -1287,7 +1287,9 @@ class AnnotationsTest(fixtures.TestBase):
             t.c.x,
             a,
             s,
-            s2
+            s2,
+            t.c.x > 1,
+            (t.c.x > 1).label(None)
         ]:
             annot = obj._annotate({})
             eq_(set([obj]), set([annot]))
diff --git a/test/sql/test_types.py b/test/sql/test_types.py
index f9ab785eda..8987743d4a 100644
--- a/test/sql/test_types.py
+++ b/test/sql/test_types.py
@@ -1306,6 +1306,23 @@ class CompileTest(fixtures.TestBase, AssertsCompiledSQL):
                 dialects.mysql.INTEGER(display_width=5), "INTEGER(5)",
                 allow_dialect_select=True)
 
+    def test_numeric_plain(self):
+        self.assert_compile(types.NUMERIC(), 'NUMERIC')
+
+    def test_numeric_precision(self):
+        self.assert_compile(types.NUMERIC(2), 'NUMERIC(2)')
+
+    def test_numeric_scale(self):
+        self.assert_compile(types.NUMERIC(2, 4), 'NUMERIC(2, 4)')
+
+    def test_decimal_plain(self):
+        self.assert_compile(types.DECIMAL(), 'DECIMAL')
+
+    def test_decimal_precision(self):
+        self.assert_compile(types.DECIMAL(2), 'DECIMAL(2)')
+
+    def test_decimal_scale(self):
+        self.assert_compile(types.DECIMAL(2, 4), 'DECIMAL(2, 4)')