Either you don't know the rule about ignoring terrible posts, or you don't know the rule that the post you replied to broke. Either way, read the rules again.
Like you said, your raid composition are not the best in the world, with that many paladins and druids around, you are probably missing some raid-wide buff/debuffs that normally a PuG would have.
If you are doing everything you are supposed to as an unholy, then the lower DPS could be just purely from raid composition. Besides, for a guild run, if you can get past bosses your guild is running without risking running enrage timer, then every DPS is doing their job.