The only time I really use Off-TV play is for the Virtual Console games. Now that Nintendo's gone HD, I'd much rather see the games as large as possible on my LCD TV. The idea of Off-TV play was really exciting to me originally, but on the gamepad HD games just feel... small. Of course, they actually ARE smaller than on a large TV, but there's something lost to the grandness of it all. Even if Zelda-U incorporated this feature, I wouldn't be using it.
If it DOES get incorporated, I would hope it's not the sole use of the gamepad while playing single-player. I would try the gamepad out if it had other things to offer, but I'm not fond of using the gamepad to play and just having the same thing happening on its screen as on the TV screen (such as the was New Mario U is). I think if Off-TV is used in Zelda-U, they need to have it be something that can be switched on and off, and not be a constant on the pad's screen if your TV is on or not.