I actually think that Williams proved a bit more, and I would be minded to favor him. Interestingly Foreman shared a ring with both of them, and indicated that their power was comparable.
For whatever it is worth, Williams resume has more substance to it. I think that he beat two ranked contenders, and drew against another, while Cooney didn't beat any. Neither man has great depth when you start to throw them into fantasy fights, but with Williams you have a bit more to work with. Granted they are both men who might well measure up better head to head, than their resumes suggest.
I'll take the guy who has wins over actual top ten contenders, as opposed to the guy who fought washed up has-beens, and never beat a single top tenner in his life except a shot Ken Norton, who only got a ranking because of his name.
He got a ranking because he beat undefeated Randall Cobb, who was coming off a win over the same Earnie Shavers who had obliterated Norton and came within a whisker of ending Holmes. That same Cobb would lose by majority decision next time out (after Norton) to Michael Dokes, who was the cat’s ass at the time. Norton deserved to be in the top 10. It wasn’t just on his name … it was his resume, topped by his most recent win, which was over a contender.
Mickey Conney had but 2 fights. You said "Conney" and the only Conney i know that boxed was Mickey. Try and keep up. If you meant "Cooney", well he sure never fought Holmes 15 rounds. To say you are loose with simple facts would be a gross understatement.
Cooney. He Blew away Norton in 1 round. Stopped Jimmy Young. Gave prime Holmes a great fight. Cleveland Williams was a can crusher and is wildly overrated on this board for some reason.
If the fight with Holmes was 12 rounds Cooney would won. Can I see Williams lasting more than 5,6 rounds with Holmes? I don't think so.