It's unlikely that there is a "cure", per se, because it affects each person differently, and it has been narrowed down to a neurological problem on the cellular level. My take is that one has to create a new pathway around the offending clump of short-circuited cells, taking care not to get them misfiring again. This takes a knowledge of how things work, then the patience to effect change on a micro level and on a daily basis for quite some time, but I'm pretty old, and my age may be a limiting factor in my rate of improvement. Much of the reason I've stuck with Harscher for the past 3+ years is because he has introduced me to several brilliant authors and theoreticians in the sports medicine world who have a deeper understanding of the body-mind relationship than most instrument teachers do. Because pro sports is such a huge industry, elite athletes receive many hours of one-on-one training in the smallest details, unlike we musicians who generally have to settle for an hour a week of instruction from somebody who may not have a clue as to how the body-mind connection really functions. I know that in the lessons I've had (many years ago, for sure), nobody ever mentioned many of the essential movement forms and positions that are now more-or-less standardized through Shearer, Berg, Iznaola and others. Harscher is familiar with all of the most recent research, and is a good diagnostician, and I found (finally) that if I followed his instructions to the letter, I fixed things. I also learned not to treat myself as a beginner, through reading Berg, who comments that change is the important constant in developing a perfect technique. Slight changes in positioning, attitude, striving for tone are essential to recreating a technique that won't let you down. Now that I've given up the ego fight and the old patterns, I find myself spending hours at a time just moving the index finger to create a round, dark juicy grape of a note; once I can do that repeatedly, I find that my index finger is much less of a problem than it was. This is applied to each digit singly, then in various combinations, and in a few short weeks, I am playing things i had given up for lost. I have created very personal goals that may be quite different from anybody else's, for professional reasons, but the achievement of each goal helps to unify the overall technique, and, especially, the CONFIDENCE that progress is being made, and that progress NEVER has to stop until one is dead or decides not to play any more.
As far as Leisner is concerned, I investigated his approach with curiosity until I heard him play, and I could hear FD in his playing, so never went in that direction. On the other hand, Jerald Harscher was a dystonic, and can now play his ass off. The stuff happening overseas is impractical for me, although it may well be very effective. There are lots of smart folks working on this, so there are more than a few capable instructors, most likely. It's important; as it turns out, recent studies posit that some 75-80% of conservatory and music school students are playing with pain and injury. These are the dystonics of tomorrow.
Lester Devoe Flamenco Negra
Lester Devoe Flamenco Blanca
Aparicio Flamenco Blanca with RMC pickup
Bartolex 7-string with RMC pickup
Giannini 7-string with Shadow pickup
Sal Pace 7-string archtop