Earlier quoted context omitted.
We originally used Microsoft Source Safe, which added the comments for us. I think Source Safe made us lock a file to make changes, which was a PITA. I think we made a lot of the decisions on where to break out code on a file by file basis because of that. Later, we moved to Perforce, which is good for larger binary files.
I would still like Git to have some kind of memory of a file being edited in some kind of branch. It would make it easier to communicate work done on the same file because you can discover what is being done to it.
`git log ` gives you the entire history of commits that touches that particular file.
edit: i suppose you mean the ability to keep track of what is being done in other unmerged branches perhaps?