The question has come up about why the Storm Father is so different in the released prelude than in the first 4 books. There has been a lot of speculation that He is lying to Gavalar. However I come at this from the perspective that the Storm Father was too frank with Gavelar and has chosen to not disclose any information to Delenar unless he asks.

In other words I take the position that the prelude gives more information than was reveled in the first 4 books -- which fits Sanderson's style of parsing out an ever more complete picture as the narrative progresses.