This would also break the design of the game, in the sense that you are now introducing whole trees that are PvE only, and that function wildly different in PvE than PvP...that is a terrible idea and terrible design.
PvP and PvE are very very different environments. It only makes that skills and abilities work differently. They could trash one spec in one aspect and leave the other unchanged if it has to be.
They're going to nerf Rage/Focus because of PvP, great, though in order to do that, when they force Smash to have a target they are negatively affecting both ACs for Knights/Warriors, on both PvE and PvP, all specs. That utter garbage.
And it's not like they can't make that work. PvE relics "know" when they can work, a Tank's guard works differently in one place or another.