I know as far as that is concerned, SE has come out and said it was intentional and working as intended. I believe it had to do with the skill animation. I am with you though. If they're gonna make the animation go off prior to the effect of the ability applying, then they need to adjust the cast time to reflect that. I have had times where my Rage of Halone ability will actually interupt after starting with two slashes because I was running between targets to rotate combos on when things wouldn't group nice.