Back in 1995 or 1996 if I remember correctly, I read an article on Keyboard magazine, which I believe had something to do with the current topic.

The article stated that Keith Emerson had felt a certain inability to perform his own music some months before the article.

The symptoms were nowhere near the "I feel numbness" status, they were more like "my mind sends the proper messages, but my fingers don't interpret them as they should, but only I can realise there is an actual difference or sluggishness in the way I perform".

The article went on about how he found a specialised piano teacher who told him "just sit on the keyboard and play". She stated that from the moment he touched the keyboard, she knew what the problem was. Not carpal tunnel syndrome but some kind of minor deterioration of the nerves, caused by years of bad stance and arm/wrist/finger position.
Even though he was a pro player he had not had the proper "education" on how to position himself for the best effect in playing but also in keeping the "stress factor" low, and to learn to in that age, was painstaking for him.

I can't exactly remember the outcome, since I read the article so long ago, but I posted this here, wondering if someone collects those back issues and can find it.
I don't have similar symptoms or an opinion to voice, It is only my little contribution to all of you that perform professionally and live out of playing an instrument. you may find something in the above that helps.

Just my 2 cents,
Theodore