I think Merecat is right. When dealing with DID apparently diving in to the trauma too soon can be really damaging. T's need to build the relationship and trust between the two of you first, and also make sure you are stable. It is dangerous to start to trying to deal with the trauma before you are stable enough to handle it. I guess when day to day life is going ok and smoothly - that is when the deeper stuff starts.

I only say this cos I was getting as frustrated as you are, and so started reading loads of books on treating trauma and realised what he was doing.