I will also add it allows for less mileage on your 7-8 best players that guys 9, 10 or even 11 can actually take on some of the load v. Butler, DePaul, or Georgetown in January and February rather than asking RJ Cole to play 34-36 minutes every night. Saves fuel in the tank for March, which may have been a core issue last year in the quick exit.
Less time on the floor also means less likely to get injured pushing your body to limit, which was what lead to the short exit the year prior (RJ concussion, Bouk cramps).
So in short, as you said it is going to be 7-8 guys in March and it should be, but have guys 9, 10, and 11 be usable in conference games has a number of benefits.