This is a fallacy…Human beings were not in existence while dinosaurs roamed the earth.If Ledlum returns, you can add him to Luis, Zuby, Wilcher, Dunlap as guys who already know the system. There still is something positive about continuity.
No to mention, Ledlum is a selfless leader and should he return, will be coming in already understanding his role.
Sure, things are not exactly the same, but long ago in the dinosaur era, college teams were built this way.