Judging by the code, this seems to be a much more rigid implementation. I've only run the unit tests and some variations of my initial examples, and everything seems to work as intended. Will look at it more closely this afternoon.

One thing that caught my attention in the patch is that gettext.c2py is removed entirely. I know that this function is not exposed in the docs or in __all__, but it still has "public scope" and it's likely used directly in the wild (googling the signature confirms this). Perhaps it should give a DeprectationWarning and delegate to _Plural?