Interview with Jeff Kaplan.

[mandydax]

This is all theorycraft, though. Nobody knows exactly what Blizzard will do yet except insiders. I'd always assumed that the reason Blizzard never had +damage on +heal gear was for PvP reasons. I don't see how you can balance it properly.

Also, they're really just in the preliminary stages of developing the new expansion. They'll have a ton of Beta Testing like they did for TBC, and there will be people like Faxmonkey showing exactly how easily abused things can be. Like for the mage's Spellsteal, they didn't originally limit it to prevent stacking of buffs and they didn't put a maximum time limit on the buffs, so he'd get 5 or 6 stacks of the Astromages Solarburn (AoE periodic fire damage ~750/3 sec each), then go into AV, blink into the middle of a bunch of Alliance, Frost Nova, and Ice Block. He's immune to them, but he does about 1500 DPS to anyone near him. Everyone seemed really unsure about a lot of the spells that were announced for TBC, but we all take them for granted now.