--of people who have evidence of neuropathy, particularly painful small-fiber types, from glucose "spiking" that would not meet the criteria for frank diabetes to most doctors, just as there are reports of similar neuropathies in those whose fasting blood sugar levels are not in the "diabetes" range, but in the "impaired glucose tolerance" range.

Interesting that you note the "reactive" hypoglycemia at 3 hours, after the glucose tolerance test was ostensibly over. I have written here in the past that when I get a glucose tolerance test, I insist on an extended one with more frequent draws--baseline, every half-hour through three hours, then at four and five hours---along with analysis of insulin as well as glucose levels. The pattern of glucose rise and fall along with lagging insulin rise and fall--in particular, an overproduction of insulin to the moderate amount of glucose one drinks in these tests causing a driving down of glucose to hypoglycemic levels in the latter part of the test--is often an indication of insulin resistance in the tissues, which is a precursor to impaired glucose metabolism. (I have experienced this for many years; it seems to run in my family, and it is one reason I am very careful with dietary composition and timing.)