> When Jon Snow finally discovers / gets outed as R+L=J, doesn't that actually HURT his claim to the North?

Expert reviewer, you might want to freshen up on the content of the books a bit. Stannis doesn't show up to save the day until Jon is treating with Mance beyond the wall - and planning on assassinating him in doing so. In the books he is doing this after the initial battle; Slynt and Thorne essentially send him to do…