The language is this sentence took me a few reads to understand. This is just a rewording.
.. tip:: The :class:`_orm.Session` doesn't actually hold onto the
:class:`_engine.Connection` object after it ends the transaction. It
gets a new :class:`_engine.Connection` from the :class:`_engine.Engine`
- when executing SQL against the database is next needed.
+ the next time it needs to execute SQL against the database.
The :class:`_orm.Session` obviously has a lot more tricks up its sleeve
than that, however understanding that it has a :meth:`_orm.Session.execute`