How is anyone supposed to know when PMR "burns out" or "self limited itself? If PMR did that, it wasn't like an on/off switch. At least, I never knew if PMR self-limited itself or not.

I did something I called "peeking under the prednisone." I would lower my dose just to see what happened. I lowered my prednisone dose gradually to determine what my lowest effective dose was. Invariably something would happen. It was some kind of pain but it was never exactly the same as my original PMR symptoms.

I told my rheumatologist that I wasn't sure if I still had PMR or not. I felt miserable. Yes, there was some pain but not anything like the original shoulder pain when I couldn't lift my arms or get out of bed without help. The uncertainty about whether or not I still had PMR was at doses less than 10 mg.

After many years on prednisone, I suggested to my rheumatologist that she only prescribed prednisone to me because maybe she thought it was what I wanted. The suggestion was that I was stuck with taking 10 mg of prednisone every day and she was responsible for feeding it to me. My rheumatologist was very patient with me!

I wanted prednisone but probably not for PMR only. In my case, there were many reasons why I took prednisone. Pain was the overall reason but I don't think I took prednisone just for PMR pain, When I started to read more about adrenal insufficiency and how people become "dependent" on prednisone, I became more and more convinced I had adrenal sufficiency, However, I must have still had PMR because my rheumatologist said I still had PMR along with "other things." She called the other things widespread systemic inflammation.

My symptoms were probably caused by both PMR and adrenal insufficiency. Actemra was prescribed for the part that was PMR. That allowed me to taper quickly down to 3 mg of prednisone. At that dose, my adrenals needed to contribute some cortisol or I was going to be miserable for the rest of my life. If my adrenals weren't going to produce enough cortisol, I was going to have widespread systemic inflammation. I came to this conclusion after I learned how cortisol "regulates" inflammation along with many other things.
https://my.clevelandclinic.org/health/articles/22187-cortisol
"Suppressing inflammation: In short spurts, cortisol can boost your immunity by limiting inflammation. However, if you have consistently high levels of cortisol, your body can get used to having too much cortisol in your blood, which can lead to inflammation and a weakened immune system."

In my opinion, you can also substitute prednisone/prednisolone for the word cortisol in the above statement.