How much research have you done on this? If you dig into the research you will see that Sarno's theory is the best explanation for these conditions. (I've suffered from one of these conditions myself, and done extensive research).
"The treatment protocol for TMS includes education, writing about emotional issues, resumption of a normal lifestyle and, for some patients, support meetings and/or psychotherapy"
For general back pain, I wouldn't be surprised if this "treatment" involves some very simple stress relief mechanism that relaxes muscles and reduces muscular pain for some people, some of the time.
The theory, however, is nonsense, and you could just as easily substitute "demons" and "exorcism" for "emotions" and psychotherapy" and get the same results. "TMS" is a made up term with no science behind it, just wilful speculation from a professional who should know better.
To suggest it has anything to do with the unremitting pain described in the OP is deeply irresponsible. It's like suggesting homeopathy for cancer. In fact it's probably worse, as it amounts to victim-blaming because the patient isn't dealing with their "repressed" rage/emotions. Awful.
And the pain isn't muscular in nature, it is neurological.
I've done extensive research into this area for 15 years, written a book about it, and published research, as well as suffering from it myself (and recovering).
Although I haven't digged very deeply into Sarno's theories, I can tell you that from what you have posted above, it is right on the money. However it's not simple 'stress relief' or 'relaxing muscles'. It's more to do with rewiring your brain through changes in behaviour.
I follow the research. Psychosocial factors have been studied to death and certainly aren't important for recovery, particularly given recovery is not a particularly common outcome (for CFS/FM at least). (If only they were, it would make recovery a lot easier.) They are, however, peddled by people giving false hope to the vulnerable and desperate.
IMO your certainty about what is or isn't the cause of all those conditions is certainly not justified. For example, how can you be so sure Sarno is "right on the money" when you admit you haven't looked into it very deeply? And Sarno's theory is very much about emotional release, that's the whole point. Gotta get that repressed rage out.
I'm actually in the process of getting a paper ready for publishing which gives an updated overall theory of the illness, plus a proposed treatment. However because I've been busy working on my business, this has sat on the back-burner for the last few months.
Also, there is so much hate out there for this kind of research that there is no way I'm going to post my name here.