My last Gruul kill offered approximately 850dps with neither CoS nor priest debuffs removing 30% spell damage.
The first trick to warlock DPS is having all available curses up, curses as I recall tick for approximately 400-500 dps with 150dps coming from curse of doom or agony. Gruul is a fight offering much movement and stunning, these dots are going to have an effect in a fight where people are immobilized.
Keep up every dot, throw in shadowbolts while everything is ticking (get DoTimer) and you've maximized warlock dps.
I would say dots over immobilization, and +30% damage. possibly heroism, SP totems and whatnot will cause extreme metre readings.
For reference this is with 1500 spell damage 10% hit +6% affliction (obtainable from crafted and heroics) wet (1210 + 150(flask) + 65(shadowP) + 35(G. arcane) + 40(oil)). When 100 fel armor, a 101 totem, 30-40 imp spirit, 95 spellstrike, and 150 icon are added things die quickly... then multiply it by 10% (CoS), 5% (misery), and 15% (shadow vuln) while everyone's stunned this simply cannot be beat.
The point of all the peak trinket damage throughout the fight is a warlock can trinket, hit +2000 spell damage, then apply all their dots over a short period of time
edit - with item changes, a favored group setup and select positioning a warlock in pre-25man gear can hit over 1000dps over the course of gruul while running an accessory curse (moonkin shadow priest shaman)
