Just to clarify, the excercise involves playing as quiet as possible a long, second line G. Then play an F scale using zero pressure and as quiet as possible up as far as you can go. I can reach a G above high C. It does not sound great, but that is not the point. When playing normally (the Haydn concerto) I do not get dizzy at all. Only during this excercise. I could probably make myself pass out if I kept pushing it. I should record myself doing this and put it on Youtube. I may encourage young drug addicted youths to seek this new high though.