Late in September, Clemson and Notre Dame made the kinds of dramatic changes that struggling teams sometimes require. Clemson benched its starting quarterback, senior Kelly Bryant, in favor of freshman Trevor Lawrence. Notre Dame replaced its own incumbent quarterback, Brandon Wimbush, with backup Ian Book.

Except Clemson and Notre Dame were not in a rut. Both teams were undefeated. Both had starting quarterbacks who, despite not playing particularly well of late, had led the teams to overwhelmingly winning records since the...