The problem I have with the wolfrider is your opponent wastes a 1/1 or some trivial card to kill it. Yes, you get 12 damage, but you don't impact the board much. With a 6/5 or something, you force your opponent to use something useful against you. You are getting 12 damage at the expense of a card that is dying next turn and whatever windfury costs you and nothing really impacting against your opponent. They still have their big cards waiting for your next play. Forcing a flamestrike, polymorph, etc hurts them and you. While you might not get that 12 damage that turn, you should still be in a decent position (unless that was all you had in your deck, and then you're likely to lose anyway).
