I'm not sure where you are going with this, do you mean you don't think that he was ever seriously ill or went to the US for treatment?
As I said, my memories of him (and we spent much time together when I was a child) were that he walked with a very heavy limp dragging his right leg, wore a boot with an iron brace (colloquially called leg irons in those days) which fastened under his knee, held his right arm bent very stiffly into his waist and so could not write, spoke with very slurred speech, suffered debilitating headaches and on the side of his body that was not paralysed he had no sensation to hot, cold or pain. He also had a scar with noticeably stitch marks running down the back of his neck and all these would have been after the operation. I also know that this whole catalogue of problems was seen by him and his whole family generally as an improvement on his original condition, which would have been called post encephalitic parkinsonism.
This is a description of encephalitis lethargica. There seems to have been an epidemic of this in the late 1920s - Typical ongoing signs of encephalitis lethargica include a spectrum of neurological symptoms such as marked sleepiness (hypersomnia), eye movement disorders (like double vision), and parkinsonian-like symptoms (tremors, stiffness, slow movement) appearing months to years later. These chronic signs are often preceded by acute, fluctuating symptoms like flu-like illness, fever, headache, confusion, and behavioural changes. 20% of the cases resulted in death. As I said above, I do personally remember he had a scar running down the back of his neck and looking at the experimental pyramidotomy treatment that Tracy Puttnam pioneered, the usual operation would have involved cutting into segment C2 of the spinal cord. The C2 vertebra is just below neck level so the scar would have been several inches long, just as I remember.
Pre-illness he had been a farm worker and I don't see why that description could not be carried forward into that Court Case or into the 1939 Register, even if he was not actively employed. I know he had friends throughout his life and they did see that he was able to go out and about. As an example, his old employer, a Mr Palmer, used to pick him up by car to take him out to follow hunts. Although I had no idea about the court case and it seems a bit out of character from what I knew of him, it obviously really happened (perhaps the behavioural changes mentioned had something to do with that?). There is no doubt he actually had this condition and I know he was unable to work from being a very young man, the area I didn't originally know about was the US treatment.
So, my interest now is how he would have got to the US, where he went once he was there and who went with him (as he was unable to travel alone). My mother (now deceased) remembers him actually going to the US but no one had ever mentioned it independently to me so it was a surprise when I realised what had happened. I obviously have no knowledge of his condition prior to the operation, but if his condition (and therefore his life generally) afterwards is any indicator, then it must have been pretty awful. The family were always huge supporters of Red Cross and Salvation Army and I think both of them had schemes to assist in cases like this, although finding records might be a problem...
This is me as a very happy little four year old with my favourite uncle Holl. You can see how he has such a stiff right arm. He died in 1976 and the cause of death was given as pneumonia.