I'm a relative new guy here - just joined a bit over a year ago. In that short period of time I have observed exactly the behavior that Dr Chien is upset over. I have three specific observations:
1) There are several regular posters here who seem to have the sole purpose of arguing and belittling others wherever and whenever they can. The ignore feature is a good start, but the responses to their posts still show up, and that can be incredibly annoying.
2) The range of experience and capability is astoundingly wide - all the way from pilots with decades of military and/or airline flight experience down to people just starting to work towards a sport pilot cert. A new person here is likely to have difficulty determining the background behind the various input he/she receives on this board.
3) Pilots as a whole will tend to be either full-time professionals in the field, or they will be people who have been relatively successful in other professional endeavors - successful enough to afford an aviation avocation. This is a recipe for combining groups of people who may often be incorrect, but will never be in doubt of their position - and they will argue their incorrect point to the death.