so why do they deviate into the world of MMA maybe as strong as they foundation is in one art, it could prehaps be that they initialyy started out in mediocre art?
I hardly consider BJJ or wrestling or Judo to be mediocre. Muay Thai/kickboxing (not american style....)certainly isn't either, and this is where you get most of your fighters.
Now, why do they go to MMA instead of staying in "x?" I dunno... why do some people choose to be nurses and others chefs? I took one look at it and thought NEAT! Then I found somewhere to train
BJJ and MMA have always been close cousins so you actually get some of the very best in the world at BJJ doing both. They win and lose some just like others. Mark Coleman, Mark Kerr, and Dan Severn were all very good wrestlers--international caliber--not necessarily international champions, but they have international experience. Matt Lindland took the silver in Greco-Roman wrestling in Sydney, Randy Couture was one of USA's very best Greco guys....
But there's not much money in it, and maybe they're looking for something new to play--new ways to use the skills they learned. Maurice Smith was an excellent K-1 fighter having fought some of the very best competition, and maybe he was looking for new ways to use the skills he learned too. I would call that exploration and "unfolding," of the highest order--"how can I use my skills in an unfamiliar venue?" Some people, like Royce Alger, can't make the transition. Some people, like Alexander Karelin, don't want to (man, would I PAY to see THAT though!)
I will say that the reason you haven't seen the very best boxers is money. Why do MMA if I can make so much more boxing, if I'm good at it?
As with any art--traditional or not--there is no end point. It's just different. My boxing coach learned to box. Then he competed for awhile, now, at late 50's early 60's something, he's teaching boxing, and I'll bet learning more and more about how to box as he's doing it. I know I've learned more about wrestling in the past 3 years than I knew when I was wrestling competitively. Am I competing in wrestling? No--but through the process of teaching some fo the things I know I've learned an awful lot about it.
Exploration and open-endedness isn't unique to anything, but has a great deal more to do with personality than an art.
I don't think your "unfolding structure," model applies beyond an individual basis. If the person can't explore new applications or refine old ones or come to a better understanding of things out of having reached a "goal," and lapsing into disinterest, that's hardly the fault of the art, or even of the coach/teacher.
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