Here is what I believe to be relatively accurate as a fan of JB and the program since the 70's. JB's comfort zone throughout the years has been playing mainly 6-7 guys. His starters, for the most part, have always played a high number of minutes, with typically a couple of guys off the bench getting "real" minutes as well. What I mean by "real" is when the game is still in doubt, not guys who get minutes in a blowout, or in garbage time, etc. JB has been on record on various occasions stating his strong belief of being able to win with 7 guys...in the college game. This is and has been his voluntary choice and style he annually chooses to play. In all of the years of watching, I can't recall routinely having a deep bench. In my opinion, even if JB had 8-9 Mickey D kids on the roster, no more than 7 would get "real" minutes as again, this is JB's preferred style of play/comfort zone.
I think over the years, with SU traditionally being a "program" type school, the upperclassman guys typically got the lion's share of those minutes. As the upperclassman moved on, it the underclassman, now upperclassman, moved into starter roles, or at least roles that found them some "real" minutes. I also believe he feels by playing only 6-7 guys, there is more continuity and consistency with the guys on the floor, giving his team the best chance of winning, which is what ultimately matters the most. However, I do feel with JB's chosen style of play, it's not unreasonable to draw a correlation to us traditionally typically having a weak or not very deep bench. There are pros and cons for sure, but JB has had a tremendous amount of success with his "system." He isn't going to change his thinking/ways, especially not a this very late stage of his coaching career.