Thanks for writing this! It's good to see more sceptical approach. Do you have any more recommendations for reading on the subject?
I've had RSI for five years now. I read Sarno, tried the Curable app, and tried on the hypothesis that my pain was psychosomatic. For my case, the benefit I've got from a more psychosomatic approach is to try to form fewer negative associations with the pain. I used to view the pain as an indication that my body was broken and that I was ruined. Now I still have the pain, but I have much less of that secondary psychological reaction to the pain, and that's greatly improved my life. I have not personally noticed a relationship between my pain and stress. I.e. it doesn't seem like I tend to feel more pain well I'm stressed.
I was also able to start doing certain activities again. My explanation for why this is is that my condition improved somewhat, and I was able to recognize from experience that certain activities in moderation wouldn't make my condition worse.
In my estimation, this article and other arguments that RSI is psychosomatic move too quickly from (true) evidence that chronic pain is a weird and mysterious to the claim that it must be psychosomatic. I worry that saying that RSI is psychosomatic feels like it explains the condition, but really doesn't explain it very well. I like that in your post you make some predictions based on your hypothesis.
My impression is that the hypothesis of myofascial trigger points has better evidence and does a better job of explaining cases of RSI, and many people who argue that RSI is largely psychosomatic are not aware of the theory of myofascial trigger points.
I should note that I'm probably biased against the hypothesis that RSI is largely psychosomatic. This is because it feels like the hypothesis trivializes my condition. Of course, I think this bias is silly, but I think I do still have it.
I also wonder if this bias could explain why I haven't got benefit from a psychosomatic approach to my RSI. I do certainly seem to meet the psychological profile of people who are susceptible to psychosomatic pain I've heard described in books and media such as Sarno's.
I've written this post with my recommendations for treatment here. I have a section on the psychological component to RSI, but I don't discuss the hypothesis that RSI could be more or less entirely psychosomatic.
If anyone's interested, here are my sources for this post. The practice of using negative visualization and contrasting to feel more gratitude is based on the stoic practice of that name. You can find it described in many stoic works, including the A Guide to the Good Life by William Irvine. This post is also based on Sam Harris's thoughts on the subject, in this video for example. I also took some inspiration and ideas from this Econ talk episode discussing A.J. Jacobs' book on gratitude
Thanks for the feedback! I guess I thought it was short and cohesive enough for those not be necessary.
You didn't even mention what might be the weirdest thing about octopuses, which is that despite their colour changing abilities, current evidence suggests they can't see in colour (Other Minds 2016).