True, we do need to keep our next 2 BBs healthy. Or, at least, try to.
As to losing BBs: look at the record. Recently, we've had some trouble, but I'm at a loss to see how Coach is to blame for it. Leggett and Quaid both got hurt before the 2015 season. Then Marshall took over and did well enough so that Leggett left, figuring he wouldn't start. Then Marshall did the same when Mills came on campus. Then Quaid did the same when Benson took over. With Custis - grades, I think - and Mills we had discipline problems. Now Benson gets hurt.
Except for Mills - and I don't think the football program is completely to blame for that - I don't see that any of this is anything but a) players choices or b) bad luck. Those aren't things that coaches have a whole lot of influence over. I'll always miss Mills; he was probably the best back Coach would have had since the Real Adrian Peterson. But we have good players on tap and every reason they'll come through.