In some files I can see a commented line, usually the last, with vim settings. Does vim read these settings? If it does, are any limitations of what kind of settings man can put there?
They're called modelines and while I'm not sure the extent you can go with them, here's a link to the vimtips wiki with some examples:
http://vim.wikia.com/wiki/Modeline_magic
help modeline
from within vim to check out the official docs.