Re
@SOC asking why ME/CFS patients are demanding evidence for high success rates before they will try a treatment, this isn't the impression I get. Many many patients have tried, and are trying, multiple treatments - often out of desperation, and often at great cost to themselves in both financial terms and health/energy terms, without demanding much evidence at all. Sometimes the treatments have helped. Sometimes they have helped at first, but then the effects have declined and/or disappeared. The same seems to occur with everything we try, at least in many people. It probably includes pacing.
I've remembered two aspects of my ME 'life' where pacing (I think) has made a very clear, long-term difference. In the mid-1990s I sometimes crumpled to the floor, devoid of strength and energy. That has not happened for a long time now, presumably thanks to pacing. In the mid-1990s-early 2000s I sometimes had to go upstairs on my hands and knees, and come down on my backside. That almost never happens now. In fact, in the last couple of years I have often been able to go up and down stairs and steps even without my walking stick. (OTOH using the stick when I need to can perhaps be included as a pacing aid.)
In the 1990s-2000s I thought that I might have to move into a bungalow, get a stairlift and/or start using a wheelchair and/or mobility scooter. These are no longer things that I am considering, apart from possibly a scooter for occasional use (if I could afford it).
I would call those definite improvements in functionality, and I put them down largely to pacing. I haven't taken any medication for my ME, other than supplements, and have been ill for 20 years.
I rarely get obvious or severe PEM now, other than mildish ones like temporary declines in sleep quantity/quality, polyuria, diarrhoea, tiredness, brain fog and weakness, but feel well quite a lot of the time - more than before, I think.
The main improvement that has eluded me is energy, although I do have spells of feeling quite energetic and being able to do quite a lot, sometimes for days in a row. Then several days of being tired and weak - but not ill.
Still not well enough to be able to do a full-time job outside the home, but I'm on the verge of being a state pensioner now!