If I'm getting ElfTengu's post, I think he's suggesting that there are some but not many. Taking it a step further, it looks like James Saville trains at least some BJJ, too. Won a couple of fights by submission.
As I said, if I'm understanding ElfTengu (and I might not be), he's suggesting that most traditional training doesn't include the things he listed that he considers the keys to being effective. But martial artists in TMA styles who do these things CAN make it work. If I'm getting it right, I can agree. I might not agree entirely with his specific criteria, but I've said many times that it's not the techniques, but the training methods that I think are the problem. And just recently in another thread, I said that I believe that most styles have internalized training philosophies. Some bad and some good.
James does more than train 'some' BJJ, he trains MMA with Caged Steel, a very good MMA gym. Ross Pearson is out of there, and they have two UFC vets Ian Freeman and Leigh Remedious.
James' Jits is awsome actually. He's also part monkey! I've known him since he was 14,watched his training and his first fights and he's one of the most talented young fighters going. He actually built a cage in his garden when he was 15 which was one of the funniest things I've ever seen. James is a good example of the fighters we see here, well rounded, well trained and supported with good skills on the ground and standing. He's fit, yes and he's entertaining all things that you'd want in an MMA fighter. He started in TKD and has added groundwork, boxing, Muay Thai and wrestling to his skill set as do all the fighters I know. He's been training for years now. Like most of us he's down to earth, theres little money in MMA in the UK, only a couple of fighters earn enough to live on and they went to America for that, we don't get hyped up about the info these fighters give us, we know them, know where they train and who they are trained by and in many cases have trained with them. Many of us train at other gyms and we have frequent 'open mats' usually for charity where we all train together, it is actually very 'homely' and small time. Proper MMA one could call it, the grass roots, people doing it because they love it sort of MMA.