Timing is important here, not career stats Cooper showed in 1990 with his gallant war with Mercer and going out on his shield against Bowe that he was bringing his "A" game. Meanwhile, before facing a still green Lewis, Mason was fighting very safe opponents. He wasn't facing anyone as "live" as 1990 Cooper. This would not be a mismatch at all. The only reason I see Mason outlasting Bert is the big size difference. Cooper's style was to go head to head and that would cost him here as he is at a big disadvantage in size and strength.
In 1990 he took on Mark Wills and Everett Martin. I never saw these fights but I read somewhere that he didn't look good against either of them and even briefly retired for several months due to a torn retina that he sustained from one of them.
Yes, both fight Mason won by 1,5 pts advantage (10 for winner, 9,5 for loser of the round) , so by 10-9 system he won these HOME fights 96-93 or 97-94. Both very close fights.
They were quality jorneymen, and had a couple of good wins. That being said, neither was ever close to top-20 and Mason struggled with them.
We're presumably picking both at their best. It's a bit disingenuous to suggest that one fighter loses to another based on overall career form. This is a one-off.
Well, they might have been top 20 at some point, but I get what you're saying. Bert Cooper wasn't any better, generally. He was a big puncher though, but his style probably suits Mason more than Martin's, for example.
Anyone really like Bert using that cross-arm defense? I was never a fan of it especially against a guy with a good left hook. Then again I'm not sure what defense is optimal or lets say highly effective for Bert anyway. So maybe the cross arm defense does not get solved by Mason early and he gets clocked. He didn't exactly face a ton of difficult styles or defenses to solve, did he? But he did have a left hook. It would have been a nice matchup and I think anyway, a nice result for Mason. The trouble is it opens the door wide open for stiffer competition. a steady diet of top 10 is not good for either guy. There certainly were other guys around capable of causing lots of problems.