I agree and disagree with parts of the statement. Practioners have a legal liability to not push the boundaries, because if they do, they open themselves up to being sued. You however cannot sue yourself, and what matters is the individuals perception of their own ability, not what others think. If you believe your ready to poke your head deeper, then do it and see where it goes. You are going to get worse before you get better, have no doubt about it, but you need to go down in order to come up, because when your down, that is when the brain learns, because its at its weakest, which means it can be manipulated by yourself providing it factual and realistic information, opposed to fictional.
Yes, your dad shot you, but that does not mean that everyone in the world is going to shoot you because they have a gun, ie. police. Factually you know that a police officer carries a weapon in the case they need it in self defense / defense of another who it is their duty to protect, not just pull it out and shoot you because your walking past them. This is the type of factual and realistic information you feed yourself when you go down from opening pandoras box. When you open it, you cannot close it, instead you have to move through it, fighting the entire way.
I don't believe there is any such thing as a person who cannot heal, because even those within the concentration camps have healed, or healed to an extent. I was actually taught and education on PTSD from a lady who was within the concentration camps, and she suffered beyond belief, and to this day struggles to talk about certain aspects, but she can make herself, and does. She is actually now a pain specialist, and one of the best on offer, likely because she has such practical experience in the field from her own suffering.
She taught me that everyone can heal, its just a matter of finding the unique aspect to each person that works for them, opposed in attempting to use some blanket statement or technique that works. A type of therapy doesn't change, it is only the method and application in which it is applied uniquely to each individual that changes. For example, the private diaries that run hidden within this forum, not one is the same in any manner, nor response from myself, because every trauma is unique to the individual, thus their thinking is unique, thus every answer, logic, solution, realism, fact and aspect is unique to the individual.
I generally put it down to laziness on therapist behalf, because they get tied into a thinking style, then attempt to use that across all patients, which for most may work some part, but those who really require that unique style, they put it within the too hard basket and instead have you coming back to pay the bills, yet give you nothing in return, except another appointment to do nothing.
I think you have nothing to lose to be honest, and would even go as far as trying to keep it public for yourself, opposed to private, because there are many people on this forum with a wealth of private experience in therapy, qualifications, medical and so forth, except they have the added bonus of experience from having PTSD themselves. There is so much experience here it really couldn't be found in any therapists office, anywhere in the world. That doesn't mean though that you don't need your therapist, because you do, as you need that face to face interaction in order to get things out that need physical contact and talk.
I say, if you believe your ready to open pandoras box and poke around batgirl, then go for it. Just remember, you are going to get worst before getting better, and that is something you must acknowledge and accept before you go heading into healing, because you need to remember it so that when your down, instead of killing yourself and running of the rails totally, you remember the commitment you made to yourself, and the acknowledgement that you are going to get worse in order to get better, so you do come up from the downs, not stay down. It really is a huge head game to take on, I know... as I have done it and succeeded, as some have also done here / doing now. It is really something you must decide, because only you know if your ready to handle it or not.