I have posted a lot about the unnecessary personal attacks on this board. Just because its DC doesn't mean you are allowed to insult to just insult.
We can get in peoples faces, tell them their ideas or opinions are really stupid, idiotic etc be as harsh as you desire. But IMHO we can and should refrain from personal attacks. Attack the idea/position, not the person.
People who think they know everything are a great annoyance to those of us who do.