Update on nerve condition
Viisited my neurologist today and the news is actually somewhat good. First, I reported that there has been no change in symptoms since March (or May?) 2008. Second, the only other thing I had to report was that the discomfort level appears to increase when I drive for extended periods of time (about 1 hour is enough to trigger it). Of course, that would suggest something "mechanical" (of which there is no other evidence).
The doctor was very pleased with the stability of the symptoms, although I am less interested in the symptoms than I am in the underlying cause (it's the scientist in me). She was even more pleased by what appears to be slight improvements in my ability to detect sensation in my feet.
This basically appears to rule out a degenerative nerve disease. Which is very good news. Plausible candidates still include: (a) vascular problem (which can stablize for periods at a time - and would be treated by the angiogram) and (b) an inappropropriate autoimmune response, which can fade/intensify over time.
Our plan of action is to continue what we are doing - which is to monitor it closely (me) and check in every 12 months or so for additional tests.