Tell that to the trigger-happy damage dealers who are risking a wipe every trash pull because they want to gogogogo!
It's not like I do this randomly for giggles; like I said: I do it to teach them a lesson, which usually means I've exhausted all other possible ways to make them understand that what they're doing is hurting the team.
Tanking can be stressful enough without having to compensate for overeager damage dealers.
I have some really ADD damage dealers in my raid group, to the point where we don't even CC things except in the EC trenches (it doesn't help that two of our three DPS are AoE dependent specs). I take it as a challenge. Granted, if they pull early and go nuts before I'm ready, I'll probably just let them die, but in general, I try pretty hard to manage every pull even with the DPS force sweeping and orbital striking everything in sight. Makes tanking more interesting. :-)