The only way to keep this discussion from going belly up is to do what Marina says and test the course format renderers, and if they are found to be flawed then file it as a BUG in Moodle Tracker.
I'm too tired to read, and not knowledgeable enough about renderers to comment, although I have discovered a wonderful way to include plugin renderers in themes thanks to Tim, so I guess he knows what he is talking about.
Have a nice weekend everyone. Please don't spend it
Don't worry be happy!