If you wait to use your buffs until Fester is off CD, you're wasting time. And it just gets back to the fact that having to idle your SMN while you wait for Rouse, Spur and Contagion to cast is all time where a BRD is keeping up full DPS.

And the parser does a real good job at accounting for DoTs. Tested it by adding up Bio damage by seeing what numbers popped up and then comparing to what the Parser gave me. Numbers are never more than 1-2% off. That difference does not account for doing 90% of DRG/MNK damage and 50-60% of BRD.

Keep in mind that, as average gear level increases, every class will see the same benefit, while SMNs pets, which account for 20%~ of damage, won't. The DPS gap will only widen over time.