Not all tanks are jerks, but enough are that I rolled a tank so I could always be sure the tank wasn't one. Tanks set the pace of the dungeon. It's really their job to set the pace to one that the healer can keep up with. It's no big deal if they pull more, as long as they don't blame the healer (or the DPS) for their screwup. Wipes happen, whatever. Throwing blame around is the dumbest thing anyone can do. Blame slows down a run more than a wipe does. If someone whines that their precious time was wasted by another player, they're wasting their own precious time by whining.
Proper tank start of dungeon behavior: "Hey, <healer>, is it okay if I go fast?" If no: go slow. Otherwise: do the dungeon in normal fast paced mode. If the healer says yes, but there are new players, explain what you are doing before you do it (example, Dzamael Darkhold: "I'm pulling everything to the back corner of the big room. Don't attack it until we get there."). Also, if there are new players, explain boss mechanics that need to be explained, but not ones that don't (example, second boss of Stone Vigil: "<ranged DPS>, can you take care of cannons? When the dragon appears in front of a cannon, use the cannon asap"). There are new players if anyone says they are new, or you see the first time bonus at the start of the dungeon.
Proper new player start of dungeon behavior: "It's my first time, please go slow." (or: "It's my first time here, but I don't mind if you go fast, just tell me things I need to know." - in this case, do not attack enemies while the tank is pulling them until they stop and are clearly done moving them.)
Proper healer start of dungeon behavior: "Go as fast as you want to." or "Please pull fast." or "Please pull slow."
It annoys me when people ignore these things when people say them, and it drives me crazy when people ignore these things and then blame someone else. Seriously, how hard is it to be polite?
tl;dr: Any tank that blames the healer for anything is a bad tank. Period, end of story.