Shout is not supposed to be anything like Dragon Roar. Dragon Roar is a high damage skill that is also used as an HP-reducer to enter the Berserk threshold. Dragon Roar's intended use, outside of lowering HP, is as a mob-killing attack. Shout, on the other hand, is used to aggro mobs, and, most importantly, stun them. The two skills are not supposed to be similar.
As much as i'd like to agree, which I do, I still think the damage is far too frail. you'd mob faster if you hit a slash blast to both sides than use shout. =_= The stun will only delay your mobbing you plan to kill them all at once as a big mob.