This is a very interesting idea. Perhaps taping a sample session with some extraordinarily easeful people and showing it to participants can help model the openness involved. I'd be game.
I am not sure that one can learn to have that kind of openness without practicing it oneself. An equally esoteric practice that might help to foster this is the Bohm Dialogue.[1]
[1]http://en.wikipedia.org/wiki/Bohm_Dialogue