Fury said he would beat Ruiz with an arm tied behind. Lol. So, the most of Tysons power seems it stayed in the combos, old Foremans arm was as powerful as he was young, for you, who would win if they fought using only one arm?
Great question. I can see people picking Old Foreman with his right arm tied behind his back. That way he can use his left to jab and push Tyson away. Tyson will have trouble adjusting because he isn't used to fighting one-armed fighters. Foreman has fought many two-armed fighters. Experience will play a role here. Foreman will still be able to use his cross-armed guard because you said his arm is now as powerful as he was young. Old Foreman's 2 arms = Young Foreman's 1 arm (oF= ½√yF²). So old Foreman will use his young/strong left arm to block Tyson's punches. I think Tyson will get outboxed early on until he realizes that Foreman's right arm is indeed tied behind his back. Tyson might think it's a sabotage since he was a keen student of military tactics and warfare. Once Tyson finds out that Foreman's peek-a-boo offence is actually a physical limitation, he will light Foreman up. Foreman will succumb to Tyson's onslaught and fight will be over.