Subjective, of course.
But where is the fun in turret casting? Or some of you think that devs don't take fun in consideration as a valid argument?
The goal is that every spec will have something fun to do while moving, and that the best players will excell either way. Exactly like KJC and AV is right now. AV is clearly a dps gain if used right, much more than a simple extra charge as stated. Timing is key.
Also, Turret is only fun when it is worth it (CB style, high risk high reward).
This limits encounters much more than moving while casting (instants, non instants, whatever)