I see. And can I ask if ALL the other "YB gigs" just happen to have been staged by YB practioners, by any chance? Hmmm? I'd suggest you think about that for a bit before you respond.
How about having someone stand quite still right in front of you, well within striking distance, and they work themselves up into a "contentrated" state right there. Meanwhile, you do your own "preparation" at the same time. And then, when they are really REALLY good and ready to strike you, they let you know loud and clear, and the test starts then. Exactly the same as your idea, but without the necessity of anyone having to run anywhere.
Incidentally, let me suggest that if you encounter any person with reasonable experience in martial arts (or even pillow-fighting, for that matter), they will calmly and efficiently, and with significant concentration on the task at hand, knock you flat on your arse first shot. And just looking at the standard "YB defensive stance", I'd be willing to bet that a simple, straight karate punch to the solar plexus will be more than sufficient to convince you you've been scammed.
Oh, one last question, petpower_2k: Did you pay the Yellow Bamboo people any money to learn this technique? If so, please write out the following sentence 100 times after class: "I WAS SCAMMED BY CONFIDENCE TRICKSTERS."