repeatedly, it appears this efo technique does not work on these sceptics that are questioning yuka.he video has gotten quite a bit of attention around the world, over half a million hits. it has raised a lot of questions. we have one of the instructors that was in this video, jenny yelkunin. does efo work? it appears it doesn't. >> actually, it does. first of all, i have to tell you, it is not self-study. it is something else we are studying by these movements that we are practicing and it is far bigger than self-defense. >> he is claiming he can seriously just use the power of his mind. >> and he can and we all can. when we ever practicing these attacks, first thing you have to have there is the intention and then realize it means if somebody gets really pissed off, he really wants to punch somebody, he crosses a line, he loses control and that's the point when it starts to work. >> when would you use this other than in this setting? >> in order to practice efo, you have to have open mind. you have to give a possibility for things you cannot quite understand. so what went wrong wit