Forgot to post my douche of the day story.
We were running Fane with three guild members (myself included), a random Archer, and this tank named "Strength" from Feral Valley, I believe (might have been Basilisk Crag - I'll have to check). We are clearing the dungeon like pros until we get to the fireball room. The Archer calls the room and on the first spawn he dies pretty quickly after going in. No big deal, we have done plenty of runs where someone has fucked up in the room and it's really not a problem. The Slayer runs in as backup and finishes it up. The Slayer from our guild says he will do the next room and we raise the Archer and defeat the boss without any other problems.
The tank makes a comment about the Archer and calls us all "bad". I ignore it as we make the run to the final boss and throw down a fire for charms and buffs. While waiting, this Lancer, Strength, proceeds to lay into the Archer about how he is terrible and shouldn't be doing the fireball room if he doesn't know how and complains about the Archer not having any purple potions (stam pots). I feel bad for the Archer but continue to ignore the Lancer while we wait for stamina. The Archer responds in kind asking what the guy's problem is and the Lancer demands that we kick the archer or he leaves. On the last fucking boss. We start discussing it in guild chat and I really feel like kicking the tank instead, just because of how big a douche he's being. He literally says something to the effect of "Giving you to 10 and I'm gone" and then proceeds to count down in party chat "10...9...8...etc.". We basically tell the guy to fuck off and leave at that point, which he does but not before counting down line-by-line from 10 to 1 first.
We decide to 4-man the last boss just for the hell of it because it is nearly impossible to find a new tank once a dungeon is in progress. We weren't really that optimistic about winning but we run in with high spirits and actually do it without any problems at all. I traded hate back and forth with the Slayer and we barely took any damage, and the hate flipping caused the boss to interrupt a lot of his own attacks. The Archer thanked us for not kicking him and said we were the coolest players he ever met through LFD on the Valley. Feels good man.
I took screenshots of everything and was debating on exposing the tank and rubbing it in his face on the official forums (childish, I know), but I probably won't. I really can't wait for the day when Lancers aren't the only tank in town.