I'm almost certain that no 5-dps team can clear cata heroic bosses except mages. The mirror images give you the time to down the boss without taking any hits. But if you take even one hit, you will die.

If you have an outstandingly raid-geared healer you can do some heroics with a geared plate DPS tanking but it will be difficult to keep threat as well as to keep them alive.

This is why my 5x boomkin team has one of the druids with an alternate bear spec and one with a resto spec.