Heavyweights overcoming size disadvantages

This doesn’t prove that weight advantage isn’t extremely important. You could do the same thing with fighters who win in spite of having inferior skills or won and were weaker then the opponent or won with less toughness or won with less IQ etc. There are many factors that lead to success no one area is insurmountable. Weight happens to be one of the main factors however.
Also the advantage of the modern fighters is not just weight it’s usually accompanied by strength height and reach while not giving up advantages in speed and endurance.

 

Valdez destroyed Cockell in 3.

 

My point is he wasn't a fringe contender.
Marciano was 28-0-0 ,and he wasnt young.

Marciano was wrapped in cotton wool for nearly all the first 3 years of his career.
Fight 32 Simmons 8-8-1
33 MItchell 7-13-3
34 Henri 13-16-1
35 Applegate 11-14-2
Prior to Layne,only Lastarza had really been a viable threat and that fight could have gone either way.

 

He was. He was ranked at one point, which I demonstrated before. Shkor was an excellent fighter to use to develop and up-and-comer.

 

Sklor had been beaten in 7 of his previous 11 fights.

 

AGAIN, making him an entirely appropriate test for an up-and-comer.