What's a "Snap Induction" ? This is something I'm planning on demonstrating soon. It's where you confuse the conscious mind suddenly by doing something different in a usually normal interaction. The momentary gap that the confusion creates enables the hypnotist to then lead or suggest the hypnotic subject into trance instantly. In a "snap" so to speak.
It can look quite dramatic and has no ill effects. A good hypnotist will always ensure that his subject is always safe.
When we do the next Street Hypnosis demo I'll record a video for you and walk you through it.
Have a great day.