--that for people who are not frankly diabetic (yet), a 2-hour glucose tolerance test with only one or two draws post-drink may not be sufficient to reveal a glucose intolerance pattern (and a lot of doctors don't know a lot about this anyway).

When I have mine done, I have the scrip written for a 4 or 5-hour glucose tolerance test, to really see the pattern over time, with draws pre-drink and at every half hour until 4 hours, and I make sure concurrent insulin levels are done. Often the insulin numbers, and how they fluctuate with the glucose numbers, are just as revealing in determining if one has insulin resistance (an early sign of glucose intolerance).