The way I see it, stream, it isn't even cheating. As long as you fulfill the function of the class, what's the big deal? It's like skipping class when you already know the material. Come to take the test, ace it, move on. Anything else is a waste of time.
Good point, i never saw it this way and there's plenty of times i skipped class because i knew i didn't have to go (well that and I'm extremely lazy and/or wanted a sleep in).