Not just anybody can play theater experiments honestly and keep the whole experience theraputic. I will use chairs too in an effort to surface the awareness of my client more to the contact edge of what ever we are working on. They often take me up on it. I find this to be very effective in bringing home just how real the whole experience is to my clients. I am not ready to call this process a seperate technique because the chair game is really just a more concrete realization of dialogue between therapist and client.
Some clients have good ability with imagination and some have poor.
Some like to play gestalt dialogue games and some don't. It all depends on the personality of the client and therapist. I guess what I am getting at here is that since Gestalt therapy is a process of dialogue, experience and awareness, fact and imagination, time and place, and finally the satisfaction of the natural hungers and thirsts of the organism re-asserting and realizing the differences between bad food and good food, then really anything that happens IN gestalt therapy IS gestalt therapy. Ignorance is a normal function of the organism. Both client and therapist have a measure of ignorance to many things.