@b0rk Also, I think if you want to share git-notes (for example to add information to existing commits, such as that it was the cause of the bug, and was fixed later), or git-replace (which can be used to connect current history with historical repo converted from some other SCM), you need to hand-craft refspec - as they both use references which are not branches.

git-scm.com/docs/git-notes
git-scm.com/docs/git-replace