"If you have two starting quarterbacks, you don't have any" is an old saying rooted in old logic. Older still, however, are Zeno's paradoxes, which include one of the earliest discussions of infinite divisibility. Nick Saban is merely extending that concept to his depth chart, and it will be revolutionary when Alabama has 16,777,216 co-starters at quarterback thirty years from now.
There are practical concerns to that kind of advanced experimentation. Blake Sims and Jacob Coker have to share a scholarship, to start, but half a class load just means more time for film review. Half a serving each at the training table is a little trickier. Sharing a twin bed is especially weird. The bathroom? Let's just say it's not Jacob Coker's week to poop.
Hey, if you wanna doubt Nick Saban, you go right ahead. The man's a champion who knows how to create winners. Invest in a good rotary saw now, Heisman Trust. We're cuttin' that sucker in half. ROLL SOLOMON.