I noted the new banner for Hammerandrails and wondered--what if someone had already gone back in time to get Robbie's ACL un-torn in an alternate an now-gone reality, where he had it torn freshman year, then sophomore year? But the wormholes opened up by changing history like that caused the tears in Purdue's football players ACLs.
This seems internally consistent. It also validates the "no free lunch with time travel" and general entropy-makes-things-worse trope that any good sci fi plot must follow.
Or maybe I'm just babbling anything whatsoever to forget about today's whitewashing.