Should "pull --rebase" try to be a little cleverer?

Hi,

last night an idea hit me: if I "git pull --rebase blabla master", it 
could be that "blabla" decided to rebase "master" already, and ATM this 
would lead to quite a few conflicts, since commits that were not mine were 
rewritten.

However, if we already have refs/remotes/blabla/master, we could DWIM the 
--rebase call to

	git rebase --onto FETCH_HEAD refs/remotes/blabla/master

Of course, this would mean that git-pull would need to source 
git-parse-remote again...

Ciao,
Dscho