> close a source file

Why would you _ever_ do that? Now that we have tabs and the wonderful single-window display, I just leave everything open. Or you could minimize instead of closing.

Well, the beauty of great software is that it doesn't force everyone to use it the same way :)

Minimising wouldn't really work, I'm not trying to hide or move TM out the way.

I'm developing a number of concurrent projects, some of which have hundreds of source files.

You can see how this would easily become unmanageable if I tried to keep every file open.

If it works for you though, great :-)