I think you're making a lot of incorrect assumptions when it comes to boxing trainers. Actually, I think you've got it all wrong. I think more and more "big-time" boxing trainers WILL start to train more MMA guys simply because it means an opportunity to make more money...period! I think if a trainer has a set price that he charges and a guy is willing to pay it, then the trainer will be more than happy to train him...whether it's a pro boxer, mixed martial artist or an average joe off the streets.
You know as well as I know that the amount a trainer gets paid is closely dependant on how much the fighter is making. If it's not a direct percentage of the fight, then the fighter is probably Oscar. It doesn't take a genius to figure out that 5% of $2 million is a little more worth your while than 5% of $10k.
Now if the trainer is out-of-work at the time, and doesn't have a fighter to prepare...I'd argue that he probably isn't a "big-time" guy...but, in the rare case that he is and is too bored counting his loot...sure, get some cash from an MMA/Average Joe.
Freddie Roach probably works with Arlovski on James Toney's days...because you know his fat ass ain't in the gym!
And I DEFINITELY don't think training boxer automatically means that it's going to be less frustrating. I mean, just because you're a boxer, that doesn't mean that you're automatically going to pick up on things...I would think that would depend more on a person's personality and ability to learn.
Come on Hype, who do you think would be easier to train to throw punches: Forrest Griffin or Oscar de la Hoya? Because isn't that who we're talking about..."big-time" trainers?
One of my old trainers, who is far from a "big-time" guy told me, that training Daniel Edouard is extremely rewarding because he "does what I ask him to." I made him clarify it, because honestly I didn't want him to think that I was lazy or wouldn't do what he asked. He did clarify it and said, "He does it because he can. I only have to say something once to him, and he's able to make the adjustment immediately." In other words, he didn't have to teach him as much as he did the rest of us.
I'm not trying to diss MMA, although I know that sometimes it seems that way. It just comes down to dollars and cents. Right now, boxing pays its people MUCH more. MUCH more.