People interested in this issue might be interested in changeset e6a33938b03f. I use parameterized unit tests in email a lot, and was annoyed by the fact that I couldn't run the tests individually using the unittest CLI. The fix for that turned out to be trivial, but by the time I figured it out, I'd already written most of the metaclass. So since the metaclass reduces the boilerplate (albeit at the cost of looking like black magic), I decided to go with it. And the metaclass at least avoids the rather questionable use of the "modify locals()" hack I was using before.