However, the end-user experience for downloading videos from iTunesU and playing it on an iOS is excellent. It is almost a one-click experience. This is just my opinion as a user.
I'm curious, on a vanilla iOS device, what application would you use to download a video on a website and have it cache onto your device?
I agree that if you don't have an iOS device, this doesn't work.
(Sorry if I'm rubbing it in too hard, you've been very gracious in this discussion.)