Simple Exploit which can really throw off what opponent's guard when they first face you.
If you're playing with an elemental shaman, have him respec before the game starts to resto, apply an earth shield to a target (part from the shaman), respec back to elemental. Earth shield stays on the target. Although I don't think it does any healing, it just falls off as soon as you get hit, but at the start they won't be able to tell if its resto or ele.
GL HF