The weird part here is why anyone would compare a nondamage-oriented Wizard power for damage! That's just plain bizarre. Hey! Disintegrate does more damage than Warlock 19 powers! It does more damage than Rogue 19 powers. It's even better than the Ranger's Wounding Whirlwind! That's sacrilegious! Wizards are totally strikers, too!
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Disintegrate may be too good of a striker power IMO for a controller. Its hard to say since virtually all of the striker dailies have additional effects outside of damage. Wounding whirlwind is actually a burst the rest seem to push, blind, daze, stun etc. Two in one shot is the only example where it only does damage, and I flat out think that power sucks for a 19 daily. Still disintegrate looks better to me than two in one shot and I don't like that.
I don't think it is relevant that with a certain path with a certain destiny its damage might blow disintegrate out of the water. A non striker should have to work for it, like take an appropriate path and destiny in order to match a non specced striker at striking. A striker should not have to work to beat out the controller in strikeing.