As far as pacing goes, it came down to the fact that sanderson had a set deadline he was obligated to adhere to.

I think RJ loved writing WoT so much that he got caught up in setting up red herrings and expanding the unimportant plotlines. I'm sure if Tor had given him strict deadlines, he would not have let, for example, CoT drag on the way it did.

Tor themselves probably encouraged RJ to drag the story on as long as he could, in order to maximize their milking of profits from the series.

Anyways, I disagree categorically with anyone who says sanderson is a better writer than RJ.