5) "why does this idea keep coming up?" [...] There must be some reason around here...
I like it because having a lot of "local x, y, z = foo.x, foo.y, foo.z" at the top of files is repetition (something I strongly dislike, good place for bugs to creep in) and is somewhat ugly.
Also just to throw another wrench in, personally I like "local x, y, z from foo" rather than "in foo", as we're copying items from foo, not putting something in it.
