There is some speculation that he may have repaired classical flutes on a part-time basis too, which might have led him to experiment. Another theory is that it was simply an inventive way of dealing with the problems of age: arthritic fingers had an easier time achieving closure with keys.
There is some conjecture that he might have occasionally fixed classical flutes on a part-time basis, which could have prompted experimentation. Another theory suggests it was merely an innovative approach to managing age-related issues: arthritic fingers found it simpler to achieve closure with keys.