--repeat skin biopsies from the same locations at eighteen months, forty months, and seventy months have shown somewhat increased nerve fiber density each time; on the last one I am back to about the 18th percentile, which certainly corresponds with re-enervation and the improvement in symptoms.

Of course, we'll never know what was normal for me before all this started, and what percentile I would have been at then.

Can you list the reference ranges from your skin biopsy? I am not aware of any changes to the numbers, but it is possible your numbers are normed to your age and gender (I am male and was 43 at time of first skin biopsy; it is known that "normal" intraepidermal nerve fiber density does decrease with age).