Isn't it patently obvious to everyone that there are two extremes for trolling?
A) In good humour, funny, light hearted. Meant to be positive in the long run by increasing the levity of the board. More people are included than excluded from the "joke". (see half of my posts).
Meant to annoy as many people as possible. Strictly negative. Brings no value to the board. Only annoys people in the long term. The "joke" excludes virtually everybody aside from the poster. (see everything RealAccountant posts)
Sure, some people like HERPDERP fall somewhere in the middle and make things confusing, but when someone it obviously in the latter category and it can be demonstrated by a large sample of worthless content then they should be banned because they suck