I dont think that cliche really applies to MMA. The days of really one dimensional fighters is on the way out. I'm not saying a "boxer" has to be an all american wrestler or abu dhabi champ but he better be real good at avoiding a takedown both in and out of the clinch able to regain his feet and versed in sub defense. Some time spent on leg and high kicks would be necessary as well. You only have to be great at one thing, but you better be good at several. I tell you a guy I'd love to see in MMA with some cross training is Jermain Taylor fighting at 170. He has the athletic ability needed as well being an awesome physical specimen.