With Warlock, I meant RShaman as a healer in that comp.
It does rely heavily on keeping Frost Shock up with UA's undispelability, and of course Fearing the 2 DPS for most of the part switching back and forth.
Heavily Offensive, but that's to be expected.
Also, the new Angel Cleave(RShaman, ShadowPriest and Ret) seems to be the new most powerful Ret combo, even after the patch.
Of course the Ret needs 1 mainhealer and 2 offhealing(for burst when going low) to keep the ret up.
http://warcraftmovies.com/movieview.php?id=180767
^--- One example of Angel Cleave pre patch.