Most of what has been said is bang on the money with special mention to Tom, Woody, Parksy, Pbudgie, Lump,and DKsize but I will add one more thing :-
People who have played the game for a few years and think they know about paintball, these are the worst of all because it is within their nature to try and teach the game, they love to play the big man, they love to feel as tho they are respected and yet, they know fack all.
The poor bastid young players who come into our sport and don't know who to listen to and who not end up being taught by some of these jerk offs and learn completetly inappropriate techniques (that are soo difficult to get rid of ) and inappropriate thinking.
Just because people have played a few years does not mean they know the game least of all, they certainly don't know how to teach it.