Let me throw this idea out there.

How about actually planning some and letting jobs focused on DoTs DoT and jobs focused on damage do damage? I'm sure that if there is a cap on DoT, you may as well deal direct damage with your heavy DPS classes instead of block a DoT class from dealing damage.

Sure, won't work very well in pugs, but you kind of have to expect 24 man pugs to be rather poor and inefficient.