I have managed to read the Blog now, having various other distractions. It is full of important points.
I had not understood, but I am sure it is the case the Boom and Bust is just another trick therapists have devised to ensure that they are always right and the patients always wrong, so needs their 'expertise'. Feeling bad? - you didn't do enough, feeling bad? - you did too much - you need to do what we say.
And I had missed that B and B is of course incompatible with the BPS psychological perpetuation gambit. Boom would only Bust if there was a non-psychological reason. It amazes me that Wessely associated himself with stuff as transparently nonsensical as this.
I note I am quoted! There are two things that interested me about altimetry. One was whether you could pick up 'movement signatures' in people with ME/CFS, which you ought to be able to do over a period of a week or so. I see that some studies have actually tried to do this, to an extent. The other was to document the push and crash relation, which would need monitoring over months. They would address two quite different questions.
I see that non-linear dynamic analysis has been used and people have extracted things like fractality. I was not aware that things had been taken that far. However, I think it is worth comparing this with the apps for birdsong recognition. The Merlin app uses this sort of complex dynamic analysis to identify maybe 5000 different species specific calls and songs mostly with great reliability. A few errors occur when the calls really are pretty much indistinguishable by ear.
In these apps not only are non-linear features analysed but they are put into recognition algorithms. I don't see that being done yet for ME/CFS but I think it has been done for Parkinson's. I suspect the problem is that those who have studied activity in ME/CFS have focused on functional significance rather than looking for a 'signature'. One or two studies do seem to hint at signatures but of course there need to be other disease controls.
Whether or not one needs huge cohorts I am not sure. Maybe so, maybe not. Another thing is that I think it would be good to look for a signature of activity that was very specific but need not be that sensitive for ME/CFS. Not everyone with Parkinson's will show a particular change in movement on starting to walk but when it is there it is instantly recognisable.
Very interesting material
@ME/CFS Skeptic, and assiduously documented.