I have to respectfully disagree. Coming from a healer's perspective, I've experienced far too many wipes and personal deaths because a DPS would pull something when my tank's CDs weren't ready, or he was out of TP or I was low on MP, etc. Whatever the case, we weren't ready. I'd heal them because they'd take a hit that only a tank should be taking and would immediately pull aggro off of one or two of the enemies because the tank, again, was not ready. And then I would die, and the party would wipe.
This game is a team effort, yes, but we all have our roles to play in a party. That's why our stats and movesets are set up the way they are. DPS can pull enemies from afar when deemed necessary, as can healers, but never normal enemies. Again, as a healer, I've seen tanks pull mobs they simply couldn't survive, no matter how many heals went out. But when not healing, I've also seen DPS and healers pull mobs that I already knew my tank could not survive, but they thought he could. And we wiped. And when asked to stop pulling things, those people responded negatively.
As for Valenth, I agree with what you did. It's a shame that certain people in the community have become this way, as it discourages new players from playing with veteran players. Hopefully SE will take note of this and go out of their way to not force veteran players to grind level 15 content again like last time in an attempt to "encourage them to play together". All that resulted in were the fastest first-time runs for new players that anyone had ever seen.