When i said 40k damage i was talking about constrictors and their needing to be killed ASAP. Second, what 3 gcds? Your only insta-cast spells are corruption and coa. Coa doesn't crit, and corruption won't crit 8k on a target without coe or haunt on it, it won't crit as much on a target without imp scorch on tow on it, not to mention with my ~20% crit shown in my stats my conflag has an actual 50%+ chance to crit without any raid buffs. Third, don't assume you'll always dot everything on your way to the crushers. Crushers can spawn one next to each other or far away from corruptor tentacles. Fourth, yes you'll do a bit more damage *on the meters* if you dot while running, but you won't necessarily fulfill the objective of phase 2 which is "kill crushers faster", especially towards the end.
First of all when mentioning the 40k damage you never said anything about constrictors you just said you could get it in 3-4 gcds, second on the training dummys with no raid buffs/haunt/SE and only lightweave proc + fel armor + 3 IotDS stacks I get 4400 crit from corruption (yes not even life tap buff). So with even simple math it should be easy for you to see that with 40% more damage and alot more spell power from raid buffs someone CAN get a 8k crit with corruption w/o aformentioned debuffs. Please do a little research before you post missinformation. It seems you appear to be defending dest for the yogg fight, but I do not think anyone was bashing it , also affliction is not as terrible in p1 and p2 of the fight like you seem to think it is. If you raid with affliction locks who do badly in the first two phases of the yogg fight send them here to get better at their class. Just please don't state that it does bad in thoes phases cause you are very wrong there.