Animation lock is no longer a threat to your movement, they could have kept 1.0's GCD by skill animation, kept the nice 1.0 skills without the risk of lock and went from there tweaking and balancing each class for PvE/PvP. i believe there was no reason other than to be different.

i know people praise the guy but i really believe Yoshi is obsessed with getting rid of anything that tanaka had a hand in.