Thats a generalization , what about thai/kick boxers , kyokushin karatekas , judokas , BJJ guys , shidokan , daidu juku , seido , ashihara , san soo and many others ??? Lots of black belts have been produced by commercial (Mc)dojos , those black belts are worst than untrained persons since they think they know how to defend themselves ( and keep telling every bodu about how good they are ) while they actually can't