Presumably you're commenting to rectify the misinformation, and you can get to the meat of it one sentence sooner if you skip the personal attack. You already know the person you're replying to doesn't read everything in front of them. Why give them more to read? Why open with a personal attack? It never makes people like you.

1) you violated the house rules, thats a complete thought, looking for 'what did I do wrong' after that misses the point

2) because that sort of thing tends to lower the level of the conversation. Sniping at each other is easier than substantive conversation and tends to crowd it

I think dang also has an explanation of moderating style and intent floating somewhere that is persuasive and interesting. If you are interested I can try to find it for you, although you might be able to find stuff using the search or reviewing his comment history