All reports at the time indicated that Kizer was not particularly good in practice, but when he got in the game, he was a different player. Remember what he looked like in the 2015 Blue-Gold game? He looked awful that day. He was a different player when he stepped onto the field against UVA.
Part of the reason he didn't run away with the QB job in 2016 was because he wasn't as sharp in practice.
Point being, if Zaire doesn't get hurt against UVA, there would not have been a 2016 QB competition.