My experience with my own "trauma work" has been its not some stand alone thing I've done for a few sessions then we are done with it. We just seem to move into talking about some traumatic stuff, things get intense, she may use a technique or two or give me some instructions to do when stuff surfaces after the session, I deal with the fallout from digging around in the past, then move into another issue for a while. Eventually we work our way back trauma again and chip away at it some more.