Sure it's praise worthy but I still wouldn't consider a name to be boasting about when ringing off reasons why a certain fighter beats another fighter. Especially since he lost almost half his fights, mostly by knockout.
At the time Mercer beat him, Bert was 22-5 (18). He's no all time great heavyweight, and the least among those I listed, but im still waiting for the list of Gibbons' great heavyweight victims.
22-5 isn't that good of a record. Especially considering he lost (almost always by stoppage) every time he stepped up in competition. Cooper was a C level fighter who had a very big punch but absolutely no skills to complement that power. His punch made him a wild card, I'll give him that. Gibbons has no notable heavyweight wins on his record. The only thing of note he did at heavyweight was to be the only man to go 15 rds with one of the best punchers and all around fighters of all time. Mercer isn't some giant here. He's the same height as Gibbons but much thicker. Gibbons is an atg in his own right. Far more skilled than Mercer which makes the difference to me here. Gibbons can take Mercer's power because he showed he could take Dempsey's power. Foot speed also plays a key role and I think Gibbons can evade Mercer and make him look bad.
Good Lord, no one is trying to say Cooper was the second coming of Rocky Marciano, BUT he was a very hard punching hot and cold fighter who when hot scared a lot of people. And back before the internet when you had to talk to guys firsthand, almost all who faced Bert or sparred with Bert commented on what a murderous puncher he was. When Mercer beat him, he was still a good scalp. I was there. I still remember. Cooper wasn't the joke he later became. And again, Cooper is but one name on Mercer's hit list... Damiani, Morrison, Ferguson, Witherspoon are some others. And those stack up nicely against Gibbons' heavyweight resume. Oh, and Garing Lane.