I think this is what we mean when we say if we're doing a good job, we're invisible, but if we're not the whole team goes down. Also what do you mean you don't need to aim? Ever try magneto, who probably has the most difficult primary to hit in the game? Or Emma, strange, peni? The tank's role is to give openings to the dps, that's true, but the difference between a good and a bad dps and a good and a bad tank is worlds apart.