If I'm Urbs, I'm playing them both. I know it's frowned upon to play two quarterbacks, though not for any reason that makes much sense. They are both good, and if one leaves OSU would be really thin at QB. So name them both starters and move right along.
I think the psychology of this is interesting. It reminds me of some situations I've seen at UW and oddly the way Badgers fans look at the basketball team in the offseason.
Each year, UW fans try to guess how the rotation will shake out. And each year, the guesses have something like nine-plus guys at 10 minutes a game. I don't think that's happened more than once or twice since Bo arrived. It's usually a core six or seven, sometimes eight. When one looks at ninth or eighth guys through the years, they don't usually do much (and when they do, it's not for good reasons). But fans want that balance. They want everyone to be good or potentially good.
The weirdest part is when the team actually has to go deep like that, fans aren't that comfortable with it. There's always complaints. Why did this guy get a lot of minutes this game and few the next? Why do the starters (usually good players), get broken up five minutes in for three subs? In-season, it seems people like when folks settle into defined roles.
I say this because in the offseason, there's a feel of play both or play everyone. We expected the best, if these guys are each their best, we've got a good issue. But it's kind of rare a QB rotation ever feels that great when it's happening. The way our brains work, we're wired to assume when something goes wrong, that another choice would've been better (as it did not go wrong in front of us). A good example is that all of last offseason, OSU fans wanted less running JT. And when the offense looked lethargic in the first half, there was a lot of asking on this board, where's the QB run. Split QB jobs are much like this. You'll always find yourself guessing.
UW's had two in my time: the Hornibrook/Houston split of 2015 and the Tolzien split of 2009.
2015: Houston started, lost the job. Hornibrook was good, then uninspiring, then started ceding drives. Fans got split, pointed out which drives were better, got granular making their cases. It wasn't fun.
2009: Tolzien was the real starter, but Curt Phillips would get the third and fourth drives in games where UW wasn't suddenly up against it. There's still arguments about how Phillips going in against Iowa "took Tolzien out of rhythm" and cost UW the game. (I don't believe it, but that's another story)
It works on occasion, when skillsets are very different and when one guy is so good at one thing, it doesn't matter that his presence tips the play (Tebow, every good wildcat-ish short yardage set).
What I'm saying is, the brain wants everyone to be as good as we hope. But in the heat of the moment, we want the dude who's gonna be the best dude. Two similar QBs means a season of second guessing (sort of 2015-ish). Not making the call now is good, as you want both guys to stay through next year, but when push comes to shove, OSU has them, a top-60 recruit and a four-star from a Texas powerhouse, that's a decent group. And of course it's all solved if the team is very, very good.
(I know this is too long, but that offseason desire for balance and in-season desire for certainty is an interesting quirk)