My T and I only discussed a dx once, in passing (GAD). I think she decided on what general "approach" to take and that was that. The dx's are for the T's, for them to decide what to treat and in what order perhaps. I was originally dx's borderline, way back in the 70's when it meant something slightly different than today (wasn't a "fad" yet :-) and my therapist at that time (a psychiatrist did the diagnosing after a one-time interview) was a student and an idiot and went on and on about how well I fit it, etc. I learned a lot from that therapist but did not get any therapy out of him :-)