s_s,
I believe d5 assembled a long post that could have been posted with a few simple sentences, so I will attempt to answer it in a few simple sentences.
I believe when you have the ability to communicate with someone anonymously, you exhibit a lot less control than you would if you were face to face with another individual.
Why?
Because the computer is not a person.
When I am driving, and someone cuts me off, I am not pissed at the driver initially, but at the car. If I pull up beside the car and give the driver the finger and he gives it back, it becomes personal. I have made mistakes, and waved when I got the finger. I deserved it. But on the computer it's a lot easier to give the finger back. There are few repercussions, other than people finding you to be an asshole that won't accept it nor admit it if you make a mistake.
In closing,
The community (and the admin) should be able to dictate the level at which a poster has become more of a liability than an asset, and that has been done recently with two posters that I know of.
So, the system is working, one simply needs to be patient.
Have fun,
Phil