I don't think it would get you KO'd any more than anyone else, traditional Jujitsu is basically the father of Japanese Martial Arts, Judo, Akido are direct derivatives of it and essentially so is Brazilian Jujitsu. Its not going to be like a Segal movie where they just walk in there and break necks and stuff but it can still be effective. The gloves could also hamper what they could do but I would say an experienced practitioner could expect to do as well as a guy who trains in Brazilian Jujitsu. Keep in mind that For Jujitsu and Akido there isn't a professional fighting forum. (there are competitions that exhibit technique and speed but both people train for it the attacker and the target) Most of there techniques can easily severely injure the opponent. (keep in mind that there are techniques from Brazilian Jujitsu that you cant use in MMA as well gouging the eyes, pressure points, neck strikes) If your doing even simple wrist techniques at speed you can easily break wrists arms etc. As far as Segal being legit, he was the first foreigner to ever run a dojo in Japan. Akido is a real martial art and can seriously mess you up, and he has been doing it most his life. (Anderson Silva also trained a bit with him a bit)