When I first started counselling nearly 20 years ago, I was so anxious to find a "correct" theory that would somehow cover each case I encountered. Now I concentrate on clients and develop a theory or even use "mini-theories" with each person.
I wouldn't say that trainees shouldn't learn about the various theories -- indeed I taught the rudiments of such theories to undergraduates at a tertiary college for more than a decade (http://www.myauz/ianr)! However, the danger with theories is that we may too easily force the experience of the client into our web of concepts, falsifying what is being said to us.
Moreover, for Christian practitioners, the secular theories have been shaped by non-christian "basic driving forces" (Dooyeweerd) that severely limit their wholesale acceptance by Christian practice. (As Christians though, we should be equally aware of where our own thought and practice is compromised by unchristian driving forces such as the dualistic motive of nature-grace.)
None of this should be interpreted as saying that theory, hypotheses, concepts and explanatory frameworks are unnecessary. But, the adoption of one set of concepts to cover all clients' difficulties is altogether too limiting.
