Given Foreman's psychological state directly after that fight I think Ali probably would have won a decision, but Big George may have planned a bit better and paced himself more, but he'd still be landing 2-3 punches less than Ali in the exchanges just due to handspeed. Ali only ever got stopped by Holmes so you just can't say Foreman would have stopped him even if he understood the rope-a-dope...the best Foreman could have done is win a decision and based on his piss poor defense in the first match I doubt you could expect that but it would be a closer fight than the first one