I think Jeffries at his best would have had what it took to stop these men inside 15 rounds. He wast prety god at breaking opponents down with a sustained body attack. I think people are right to identify Conn as the greatest threat to him.
Actually judging footage of the era and the poor ass footage of Jeffries that exists (except from the Johnson fight of course) I actually have little doubt that an on song John Conteh could well box Jeff's head off. His short reach was never much of an issue and his left hand is one of the most varied and elegant of all time, but it could hamper him as Jeff' has less ground to cover to smother him and bust him up. Jeffries late stoppage, he's (IIRC) a bigger heavy than Conteh ever faced and even at his very best there's always the chance Conteh slips just a bit as the fight goes on, so I'll pick a strong, durable and fit 20 round fighter like Jeffries to get to him late, but I'm not sure that just because he's bigger than Yaqui Lopez that he'd do much better than him. And that was Conteh at his one handed best. Even if Conteh is wearing bigger gloves than Jeff' was used to getting smacked about with his boxing ability will be unlike anything Jeffries has ever seen. To put it into context I'd pick him to school Corbett over 15 or 20 rounds. I'd probably pick Conteh over a fight to the finish if his hands stand up; he'd twat Corbett silly. Fitz knocks Conteh out.
Jeffries KO's Moore and Foster. I think Conn can last the 15 and eek out the decision, tho Jeffries would be coming on. Spinks has the best chance here. I like his movement and selective aggression. He really fought with a nice, sometimes sophisticated, blend of offense and defense. I think he's just too developed for Jeffries, has more than enough pop and was durable.
I would regard Conn as the greater threat, if only because I can be certain that he will be comfortable fighting Jeffries psychologicaly.
Archie Moore's record against men above 200lb is 22-1 with 19 knockouts. Why are you people so sure Jeffries beats him?
he has been knocked out a lot in his career. Jeffries is a lot bigger than him and knocked out the arguably more durable ruby fitzsimmons.