That would track for me. One of them is, I assume, trained, skilled at fighting, and the other isn't. Buhcooz having giant muscles doesn't necessarily mean you're good at combat. Particularly when up against a person who is trained to fight like a bee and dance like a Butterfree.

Not surprising. Anyone at the elite level of their sport trains very specifically for that sport. It rarely translates to performing at the elite level in another sport, esp not bodybuilding to fighting

It's not surprising. I've heard similar stories. And the one who trained specifically for that type of event won. Fighting is about so much more than muscle, of course. And not to mention that too much muscle probably even gives you less agility. Also their muscles are trained for strength, not speed.

It's not the muscle mass as such but the ability to make good use of it?

Not surprising

not surprising, a trained fighter knows that winning is as much about things like footwork, balance, and technique as it is pure strength