rebase --continue confusion

I ran into a conflict while running 'git rebase branch1 branch2'. So I edited the file and resolved the conflicts, and then ran 'git add <file>; git rebase --continue'. This printed out a message 'No changes - did you forget to use git add?'. I thought 'No, I'm pretty sure I ran git add' and I assumed I had run into a bug in git because I didn't see how this conflict was different than any others I had successfully resolved. The next time this problem came up, the light finally came on and I realized that I should just run 'git rebase --skip' because when I resolved the conflicts, I had basically undone all changes that the patch would introduce.

OK, so there isn't a bug in git, but since then I've seen co-workers stumped by this same problem. So maybe it would help to clarify the message? Maybe something like "The index is in the same state as it was before the patch was applied - refusing to make an empty commit. Did you forget to use 'git add'? Or maybe you should use 'git rebase --skip'?"

Dale