Frank is not losing 10 mins a game.
Maybe he goes from 38 to 35, or even 33, but barring injury, he’s still getting a crapton of minutes as a Senior starting PG playing for JB.
Dion and MCW both were highly acclaimed Frosh G’s - who had veteran guys entrenched ahead of them, and those guys got almost ALL the minutes.
You know how Boeheim do.
I think it's honestly one of the more interesting questions on this team. I tend to feel as you do that Frank will play a ton but I do think there are legitimate scenarios where Frank is closer to 29-30 mins.
For one, veteran guards are exceedingly valuable -- we know this and JB obviously knows this.. BUT JB has shown he's not afriad to use a more equitable rotation if he believes he has the talent. In 11-12, Scoop (a 5th year at this point) went from 32 to 25 mpg and it wasn't because we Dion. In 98-99, Griff ( a junior with two years of pretty solid minutes) lost minutes to Shump and Bland. If Carey comes in and is a guy JB trusts, he'll see the floor some.
Secondly, I don't see those minutes coming out of Battle's total very much. Could see him dropping to more like 35, but I still see him on the floor most of the game every game. So if they're going to give Carey any run, it's going to come from Frank, IMO.
Third, you cited Dion and MCW, but if you look at their seasons, Dion still played 16 mpg despite not being in great condition and telling JB to f-off at one point. MCW, as you point out, clearly took a back seat (10 mpg in 26 out of 37 games) but he was the fourth guard, not the third and was playing behind Scoop (5th year), Triche third year and Waiters who was only in his second year but was arguably the best player on that team and wound up going 3rd in the draft. That's an exceptionally crowded backcourt.
So I think it really comes down to how much does JB trust Carey? Does he see what he wants to see defensively? Does he make good decisions? Does he have the talent and skill set to add something that Frank and/or Battle don't?
If those questions aren't answered positive in Carey's favor, then yeah, I agree, not a guy who's going to pull 20 mpg in place of Frank and Battle. But if he is playing at a solid level, then I would see JB trying to get him 15 a game -- 3-4 mins from Battle and another 9-10 from Frank.
I could see either scenario playing out, but if I had to bet I'd suggest we'll see Carey on the floor for decent chunks of real games.