Gary Alexander is a legend. Does that mean he's good at what he does? Probably, but what is it he does? Be a big white guy who has a mean streak and likes to use his waki-waki karate to prove that big guys can hurt people. I've never been impressed by him at all. Just because something is claiming Okinawan karate doesn't mean its worth a damn. All things are not equal, from people to MAs styles. I do know that his bro, who use to be an Army active duty "spook" type, somehow got the DOD to invest in studies concerning no-touch K.O.s and making a goats heart stop, via long distance just by thinking about it. Yep, two more geniuses who have that Jedi mind trick on weaker wills going for them. As for Tatsuo. IMO Isshin is a nominal style created by the most nominal of the Shimabuku brothers. From the faulty fist form to the diluted forms. Neither here nor there. If you work with anything long enough you can make it work though. Just opinions.