Actually stealth seems to be correct and i believe its his right to point something out that is incorrect, it's a think called free speech and forms the ground for a reasoned society. Coming to my point , I too took out time to go through astar's notes. While others were good , I saw quite a few anomalies and they to coincide with those pointed out by stealth.
Secondly, from what the topic is about, I believe stealth has the right to show his agitation as his exams are just around the corner and if you feed in wrong info esp over a topic that needs reinforcement, those agitations are bound to expressed.