Quote Originally Posted by Katana190 View Post
I'm struggling to see the point here.

Even if it could move and cast without being interrupted, it's aggro build up would be so much slower like Tint mentioned, it may as well be made instant, and then we come to the conclusion of DRK.
That would depend solely on the design of the abilities. Tanks; in general, aren't supposed to generate enmity from dishing out raw/superior damage, but generate it through abilities that have increased enmity generation and enmity control. Design a few spells for a caster designed tank and that problem goes away.