Quote Originally Posted by Dwill View Post
The amount of people who do not know how to DPS far surpasses the amount of people that don't know how to tank.
Not necessarily true, the key difference is that a bad DPS can go a long way while a bad tank reaches a point where they just can't continue any more. Lvl 50 will see far more bad DPS the tanks but lvl 25-49 will make anyone weep with how bad some tanks can be. (lvl 15-25 doesn't even need a tank)

Regardless of that though, threat management is a team effort while dps checks (depending on how they are tuned) is focused only at a certain role. If the tanks and healers had a part to play (say position mobs to increase DPS uptime) then the dps check would have meaning with team based content but that doesn't seem to be what the OP is asking for.