>> You don't, but use of assert statements seems a hell of a lot more
    >> Pythonic to me than all the assert* or fail* method names which I can
    >> never remember.

    Antoine> 1. they are optimized away in "-Oxxx" mode

As far as I can tell for Python itself we never use -O while running unit
tests. 

    Antoine> 2. they don't provide good reporting in case of failure

I've never had a problem with that.  It yields a perfectly useful traceback,
and in the case of the nose package at least, it does the right thing with
it.

In any case, your test machinery will have to catch AssertionError
exceptions anyway.