Simply because I didn't update the doc string :)

I don't really want to put a version number on this file, since it isn't MSVC 14.0 specific - it's MSVC 14 and all future versions. We don't check the build version anymore, though get_build_version() is still there (hardcoded to 14.0)

As you say, the existing modules are legacy, so I wonder what would be useful from them? They refer to compilers that aren't available and won't be useful for Python 3.5 to the extent that I'd really like to discourage using them. The modules themselves are undocumented and were not available on other platforms, so any code using them should be protecting themselves against ImportError already, and they're going to be broken anyway so they may as well break early.

But my main question is why would you still need the old versions around, given that compatibility is already broken?