His time spent in the the Maer's manse I already was enjoying less than his general University hijinks, but it was still passably fine. The entire Felurian episode though was just too far gone. I at first assumed it was a dream or vision of some sort that would soon end, and when it didn't I thought well surely it will at least be a quick jaunt in the land of the Fae. That it continued to last for chapters on end just destroyed my goodwill for the book.
I didn't particularly mind the Adem bit as much, though it was a bit rote. Felurian however I just can't get over. That section moved Wise Man's Fear from my clear favorite of the year to just a passably good novel. Which, as silvercue mentioned, is a shame as I absolutely loved TNotW.