In recent PEP 451-related discussions, the subject of reloading has come up multiple times.  Most recently, PJE suggested that reload semantics are under-specified (and under-tested). [1][2]

It may be worth adding a dedicated section on reloading to the reference doc.  As evidenced by that email thread (and issue #19413), there are some reload semantics that should be specified (and tested) but aren't.

While reload has a less prominent place in Python 3 (no longer a builtin), it is still a long-standing feature of the import system which gets used at more than just the interactive prompt.  I'd hate to see more issues like 19413 pop up later because of under-specification.  Furthermore, it would likely help other implementations pre-3.3 (a.k.a. pre-importlib) cover reload corner cases.

[1] https://mail.python.org/pipermail/python-dev/2013-October/129868.html
[2] https://mail.python.org/pipermail/python-dev/2013-October/129971.html