Cliff Judge

I guess my main point is that the skill of being able to "ride" nage's technique such that you give yourself to the technique, but retain control of your fall, is one of the most valuable skills Aikido training can offer.

I think the mindset that uke's job is to challenge or test nage's technique is counterproductive to developing that skill. Certainly, weak attacks that are uncommitted, and a sort of "falling away" from an unconnected nage can be counterproductive too.

About this arrogant student - is his technique actually very good? If it is then, well, that sucks for him that he has such a challenge developing humility. I'd be more concerned if he tended to resist everyone else's technique while insisting that his always work no matter what. That's a bigger concern for me - the person who refuses to let anyone else's technique work, while not caring what his partner's boundaries are when it is his turn to be nage, because he must always be correct. So he resorts to use of muscle and harder atemi than his uke may be comfortable with. This is the kind of personality I worry about in high-resistance environments.