I just got off of a month long ban for flaming and trolling people who I thought were ignorant. When in reality, it was me being ignorant for replying to them in the first place. The biggest thing I've learned is if you feel angry about someone's post, then don't reply to them AT ALL, it'll only turn out terribly. I think I've learned what "constructive posting" is from my last ban on a deeper level, and I think because of it; I won't be trying to defend my opinion much anymore, or try to shoot anyone else's down in a fit of nerd-rage.
I think many people can learn from what I've experienced as well as...READ STICKIES! For the love of god, before posting please take the time to research the VAST amount of GW2 knowledge on the lovely internet. You can load your guns after you've done that. Remember: opinions =/= assumptions. I can honestly say that ANet is the only games developer who's this open with their development process, and because of this there's a ton of information about GW2 out there.