The way I see it, MMA and Pro Wrestling are two completely different animals, coming down to two questions. Question #1: Are you actually attempting to hurt your opponent? Question #2: Do the two fighters in the ring truly not know without a doubt which one will have victory at the end? If the answer is yes to both, it's MMA, if not, it's Pro Wrestling. That being said, I frankly classify wrestling as a form of martial art and most pro wrestlers these days have some background or at least some showing in traditional martial arts. Every one of them has their own gimmick and move-set, so if one of them has an MMA background, why not? I seem to recall MVP has a varied move-set that could be classified as MMA material if it were all legit.

I guess it all comes down to character. I think each must decide for himself as to what works best with the character and story.