If that really was the reason for the Onslaught change then that would have been the laziest, most creatively bankrupt implementation of feedback I have seen in a long time. Instead of leaving Onslaught as it is, an actual gap closer, and designing 1 or 2 new oGCDs to make warrior's filler phase less boring (and we all know warrior is not exactly lacking in empty hotbar space) they simply turn Onslaught into the same thing that every other tank has...
It doesn't even look good as a filler oGCD, charging the boss while you're already right in front of it just looks downright goofy, it always has.
