I find knowing the significance of symptoms and response to treatment be important for therapy. The specific label isn't important and if I don't quite meet dx. criteria, I don't care. My pdoc only used the specific dx. when I need documentation for accommodations. I did find the PTSD diagnosis helpful because it gave direction for therapy. Generally I think short-term CBT or IPSRT treatments tailored to each patient to be ideal, but in PTSD treatment, it's important to focus on the trauma. It's nice to know that is not only ok but necessary.