Anna,
You seem to be asking the following questions:
(1) Are the people to whom I referred actually the leading thinkers and writers in Gestalt therapy?
(2) Is Gestalt therapy the best theoretical perspective in the field of clinical psychology?
(3) Are not all clinical perspectives the same, with mere lexical/semantic differences?
(4) If psychotherapy actually works, why is there still suffering and madness in the world?

The answer to the first question is yes. They are not all of them; I claimed they were among them. There is Gary Yontef, who wrote the basic article on Gestalt therapy for Corsini's book. Edwin Nevis, who was a co-founder of the Gestalt Insitute of Cleveland and now heads up the Gestalt International Study Center at Cape Cod; he taught at MIT's Sloan School of Management for years. Others are Sylvia Crocker, whose collection of essays in her book, A Well-Lived Life, is on it's way to becoming a classic in Gestalt literature, Peter Philippson of the Manchester Gestalt Center, Brian O'Neill, the moderator of this forum, Malcolm Parlett (editor of the British Gestalt Journal and Joe Melnick, editor of Gestalt Review, Margherita Lobb director of the Istituto di Gestalt (Italy), Philip Lichtenberg, co-director of the Gestalt Institute of Philadelphia - among many others.

The answer to the second question is that I believe Gestalt therapy is the most comprehensive theory, and one capable of assimilating the most from other theoretical perspectives. It is phenomenological (thus cognitive and behavioral, but thus so rooted in a current experience of the client), dialogical (thus interpersonal and relational), field relevant (thus multi-systemic and including all things having effect - memory of the past and expectation of the future). There is a fluid methodology, and the training process has several approaches (see an article by Brian O'Neill, Jay Levin, and myself called "Training and Ethics" in Gestalt! - www.g-gej.org - for a description of these).

Your next question seems to be in favor of the theory of common factors, but if so, you misunderstand what common factors proponents are saying. The common factors people would claim that all therapies yield similarly effective results, but they do not claim that all therapies merely change the words around. In fact, one of the elements that makes for an effective therapist is that he or she is organized by a distinct and salient theoretical approach. There may be common elements among the various clinical perspectives (I happen to believe that is so), but the way in which these common factors are constructed, organized, and manifest is not the same. It is also not true that every clinical perspective embodies all, or the same, common factors.

Finally, you ask an old question: if God is loving and all powerful, why is there suffering? If psychotherapy actually works, why is there madness? If I could answer that, I'd be rich and famous. Perhaps it's good enough to realize, as M.C. Dillon has said in the introduction to his book, Merleau-Ponty's Ontology, that any theory of knowing must allow for partial knowlege.

Philip Brownell, M.Div., Psy.D.
Sr. Editor, Gestalt! (www.g-gej.org)
Clinical Psychologist, Bermuda