To the extent Quinn's ankle is TBD until kickoff (which I think is likely the case), I don't think Sark's approach this week is that complicated. Quinn has played multiple OU games, @ Bama, Big 12 Championship, UW playoff game and @ Michigan. He has the big game road experience any head coach would value whereas Arch has zero. Of all games I have no doubt Sark really wants Quinn to play this game. Now, if he's completely ineffective because he gets in and can't move/plant and we are struggling, I'll be shocked if he doesn't take him out.
Kentucky was odd but we could run the ball at will as long as we weren't fumbling. He didn't really need Quinn to do anything and I don't think he ever actually thought the game was in question. This week is different.
In sum, I fully expect Quinn to start this game unless he flat out can't go but I also have zero doubt Arch is getting a ton of starter reps this week preparing to play (particularly considering Quinn is probably getting limited work to maximize healing before Saturday).