Should Jeffries crouch or go upright against these greats?

I think that 6' 1'' is most likley, perhps 6' 1'' 1/2.

 

He certainly looks no taller than Fitz in their ring hand shake.

 

I will not use the 1903-04 version of Jeffries that Fitz cleaned up offensively in this matchup because the sky is the limit in how good he was by that stage. The improvements in those fights can’t be proven because we don’t have film of him at that stage, though I’ve heard that Jeffries-Munroe was filmed and actually watched by Dempsey around 1960.

Upright Jeffries of 1902 and prior was the Jeffries that was very aggressive but usually didn’t really care about getting hit. A big risk taker, to say the least, and that’s what largely earned his iron man image.

Crouching Jeffries was a solid technician with competent defense, but was far from perfect and still vulnerable to being outboxed by quick movement oriented fighters on the backfoot.

John L Sullivan: crouch, can’t risk taking many shots from Sullivan even with Jeff’s sturdy chin.
Peter Jackson: upright, try to overpower Jackson instead of box him.
Jack Johnson: upright, try to dig those hooks to the body and wear Johnson out in the clinch if he even could. Make it a brawl.
Sam Langford: upright, impose your size and go to the body like against Fitzsimmons. I doubt Sam hits any harder than Fitz who gave Jeffries everything and the kitchen sink.
Jack Dempsey:upright, same reason as Langford.
Gene Tunney: upright, try to overpower Tunney and go to the body instead of box him.
Joe Louis: crouch, Louis has notably struggled with the crouch on a few occasions.
Ezzard Charles: upright, don’t try and box with Charles, impose your huge size advantage and hunt him down.
Rocky Marciano: upright, same as Charles.
Sonny Liston: crouch, his only real method of survival here is trying to counter Sonny, or be as defensively sound as possible until those later rounds
Muhammad Ali: crouch, he’s kind of ****ed here
Joe Frazier: upright, try and be aggressive and impose your size on Joe.
George Foreman: crouch, same as Sonny.
Larry Holmes: crouch, kinda ****ed here too
Mike Tyson: crouch, same here
Evander Holyfield: upright, I’m curious if a bigger version of Jeffries might somehow have success against cruiserweight or early HW Evander, probably not.
Lennox Lewis: crouch, ****ed here as well.

 

Great Post @cross_trainer you could learn something.