I guess that is also due to the fact that the controls are wireless? Moltov said he also noticed some lag when he still played with classic controller via Wii Mote.
Yes.
The Game Pad is always around 2 frames behind what's actually happening in the system, so Nintendo thought it would be a good idea to add several frames of lag to the television screen in order to be synchronized with the Game Pad. This affects ALL Virtual Console games on the Wii U. Not just Ocarina of Time.
Honestly, I can only see this version being used for practicing things due to the save state feature. Even then, its not viable because the input lag would throw off your timing in an actual run.