You can't do 170 DPS in a setup that's also capable of serving as secondary tank. Notice in the video that the guy has like 4k HP. He'll also be unable to wear endgame tanking gear because it requires you to be WAR or PLD, and he won't be able to hold aggro at all due to being marauder instead of warrior. It's basically like a WoW fury warrior; you could taunt the mob and maybe last a few hits, but you opt out of being a tank when you build for real DPS. If you want to remain capable of tanking reasonably, you won't do more than maybe 100-120 DPS.
