Honestly willix, you're being a Negative Nancy. If I could dislike your post, I would.
Paired with lifeblood, healing wave can get you through some sticky situations where you cannot bandage.
As Nollix said, goblin is far better for the extra mobility. On Alliance dwarves are the best because of they have extra expertise gained when using maces, stoneform (great because you are a bit squishy), as well as frost resist which is very effective against mages.
Imo you can do well in BG's if you play smart and know your limits. They have really good burst -- on my enhance shammy I can do 800-1k damage in 2 or 3 globals but after that your damage is not so great. If you use earthbind totem wisely, you should be okay. The 1 second ghost wolf is very nice as well and it allows you to do alot compared to a 2 second cast time. A more veteran shaman may opt to spec into flurry for the increased damage but it's situational because you're giving up mobility.
I might add that they make decent FC's as well, if you have a proper set and utilize your shield for more defensive capability. The ability to kite as well as having decent burst is very nice on D, especially for killing rogues.
Their weakest point is in mid fights because it would be very difficult to get to your enemy, but you have a chance as a goblin with the rocket jump.
tl;dr: they have good utility (purge and cleanse spirit are very nice) but you have to be smart and play your cards right to not be a burden to your team. Enhance shamans are really not as bad as some people like willix make them out to be.
Here's a BiS enhance shaman armory:
http://us.battle.net/wow/en/character/elune/Feelaleaf/advanced
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