I'm going to have to go on and say.
Removing move while casting was the biggest step back in development I've ever seen. I don't have any clue what Blizzard was thinking with this change.
Melee can still train and not ever cast. Hunters can still cast and jump in circles. Casters are Rooted in place can be kicked and silenced and probably get off the least amount of damage in PvP as a result of this.
Not only that but Blizzard gave HUNTERS of all classes the ability that decides whether or not Casters get to DPS on the move in PvE.
What was Blizzard thinking.