Berserkers already out-AoE warriors even with just their epics and sorcers of equal rank. They don't need any additional AoE DPS.
Warrior is already stumped on dps field anyway, and zerker is pretty much a curiousity class only as is. If you whip it FS5s and crap, it's still far beneath most other classes on dps, and usually you don't really look at any specific situation and think "hmm, I could use a zerker here!", since a warrior with couple angerV's already handles just about everything.
Suggesting the whole thing since zerker could be more of ae wreckage than they are atm, making them an option for others than the already-got-all-other-classes-T4'd-and-I-got-brell-serilis-rotting-all-the-time-top-end-crowd. Some guy said that 4.0 zerker with sorc50 was doing 18k or something with the ae proc. Warr with UC does 4k per ae proc, and can whip total of 6 of those in if necessary, which is more than enough to deal with T3/T4 adds (unless your team is insane single target dps, but at that point the fights are clearly so trivial to you anyway that the adds can be dealt with afterwards). Zerker just fails to offer anything that you can't have other classes also do, usually better as well.