I tried it several times when I was in therapy and I had great success with it. Personally, I afraid that they would hypnotise me into clucking like a chicken or make me forget the number 7 or some such silly thing. But actually I was aware of everything the therapist was saying, I was aware of my surroundings and I remember everything that happened very clearly. I've heard it doesn't work for some people, but as I said, it worked wonders for me.
To Englishman: HEY! I get it!! Stairs right? Simple things amuse simple minds . . . .