Earlier quoted context omitted.
I actually managed to contribute to it once, via the mailing list. This doesn't really invalidate (1), but maybe they just don't want GitHub-style forks ("modifying the supplied code 'in place' is something that we discourage").
It's unavoidable with open source. Take any project with daily tarballs and mailing list diffs and you can probably even code a solution that will transform it to a git repo. Actually a git repo is not that different from a tarball webshare with a shell client for diffs etc.
Still, I'm not sure of the value in doing this kind of thing. The licensing schemes where you can't use the projects name in derivatives made sense: poor knockoffs can hurt image and adoption. Yet, people not wanting code to be used so easily probably shouldn't be open licensing it in the first place. These people are weird lol...