Little known fact: Old Foreman was merely Young Foreman in a fake old-person suit. The SOB hadn't aged a day since Zaire. "Just as planned..."
The Cooney fight has the same results. He catches Moorer alot earlier with the same results he had in their actual fight. The only thing that may buy Moorer some time is him being a south paw. Holyfield is interesting. Holyfield had a grade A chin. Prime Holyfield vs Prime Foreman could be it's own thread. I can't see him winning a decision against Holyfield which means he would have to stop him.
Comeback Foreman was "old" for his era but he could have certainly gotten in better shape than he did. He was 38 when he launched his come back but was pretty obese and never really trimmed up. A 38 year old athlete today with the right training plan could get the visual body at least of someone in their 20s.