Roy's health could improve by losing some of that fat. I would bet he doesn't have the best lipid profile among other thing. If you want to call that "fit" then ok. He's got decent cardio and strength for his size and for what his sport is but i could probably smoke him in most sports outside of the ring and yes i include weight lifting in that despite his weight advantage over me and i'm both older than him and not a professional athlete.
Also this was asserted in the original post and i see nothing about Roy Nelson that would disprove this. The thread is not about if a fat guy can be athletic or strong or have good cardio.
"The term "fat but fit" refers to the alluring theory that if people are obese but all their other metabolic factors such as blood pressure and blood sugar are within recommended limits then the extra weight will not be harmful."
So yeah you're wrong and i'm right.