Victor's argument makes sense to me. What I'd be inclined to do is shout at the reader a bit in the traceback header by making it:

    Traceback (most recent call FIRST):

And put a comment in the source code with the gist of what Victor wrote above (i.e. internal state may be corrupted, we do the best we can with what we've got, and that means printing the traceback from the inside out)