Last session in LA, we did a sequence that released our psoas. Toward the last section of it you had us do a sit up with our hands behind our head. Usually I can do sit-ups fine with my hands extended out toward my feet. I knew that this time, I couldn’t even find the nerves to send a message. Why was this? I have tried to recreate this in my own practice but haven’t been successful. I have pretty strong abs. and a pretty strong psoas. I had 11 abdominal surgeries when I was young, mostly before having two children. I’m guessing it’s a neuromuscular connection and a certain section of the muscle fibers that I do not access.
I believe your psoas understanding is good. Often releasing it makes it work as independent segments rather than as a whole. So spine must curl up when that happens. If you are strong but using all the muscle together that could explain disorientation. I suspect that is the case after your history.