It seems my experience is a bit different here but out of 100s of DF runs, I've only ran into a handful of complete assholes. I'm inclined to believe that the majority of the problems people run into partially stem from the attitudes that they themselves bring into the party. How many parties start up and no one says hey? Or end without anyone saying good run/thanks for the party? How many people on here think it's the other guys fault, without making any effort of their own to be friendly from the get-go?

That's why I make sure to always start a run with some sort of greeting, I mean if you're a tank and consider yourself the "leader" of the party, then isn't it important for the "leader" to set the mood and lead by example? It's all about perspective imo, come in with a friendly demeanor and more often than not, it'll rub off. And from my experiences over the 11~ years I've been tanking, a little friendliness at the start can go a long way =D.