A lot of people are down on Clemency in this thread.

As someone who mained WHM for all of 2.x and switched to tank for the expansion, I feel that Clemency is one of the best skills in the game. Jesus, the amount of lives I've saved with it as the tank is unreal. And let's not even talk about all the DF groups wherein the healer died on a boss and it'd have been a wipe if I were any other tank class.