Hi amazingcharis,
I still remember when BPD first raised it's head two decades ago. I went into a bookstore I came across "Games people play" by Eric Burne who established Transference based therapy. I did not really get it at the time, did not understand what I was dealing with but the small book somehow spoke to me. He had quite some impact on other forms of therapy including DBT.
Doing comparative studies of therapy is very hard as it takes very long, takes large numbers and is fraught with bias. Based on what we know from many incl. some large and long term studies DBT is the gold standard and there are few others (maybe Schema) that seem to gaining traction. This is when comparing therapy schools.
Now any individual pwBPD and every individual T is different and these factors may well be in practice more significant than theoretical differences between schools.
BPD is multi-factorial and DBT is quite good in covering many aspects of it. Also DBT schooled T's are generally more knowledgeable about BPD and have a BPD focused backup system.
One of the key aspects of BPD is that it is a condition around emotional regulation problems. The pwBPD has emotional problems and some overly loud and confused emotions also are transfered on the people close to the pwBPD. A transference based T will be very aware of such things happening and can help the patient to improve their reactions. Having said this DBT and also this board is focused very much on validation. A DBT T practicing validation will be very transference focused. We as partners when we validate also should pay close attention to transference. Even more important when we are attacked we need to be aware of transference as the emotional transference through invalidation is the main driver in our relationship conflicts. (I have a related graphic here:
https://bpdfamily.com/message_board/index.php?topic=221022.msg12411502#msg12411502 ). A T focused on transference will be able to build a good relationship with a pwBPD (DBT starts with validation to build relationship) and a solid relationship will always be a good foundation for a therapy - you mention a one year time-frame in the study you looked at which is quite short. We all know however one needs more than a close relationship with a pwBPD to manage over a long time - boundaries spring to mind.
DBT is a more comprehensive framework for BPD covering self care behavior, boundaries etc... .A BPD knowledgeable T coming from a transference school may still have a big positive impact - again T is one-to-one learning and individual variations can dominate the "expected" result easily.
