I don't think that you need that many carbs to fuel a workout. I've been running since 2009 or maybe the last week of 2008 and have maybe 6-8 oz of skim milk (ok, sometimes I'm *really* lazy and just swill it out of the bottle...) to run 3 miles. It's not an hour but I push myself as hard as I can most of the time and generally see a "predicted high" about a mile in, as the milk hits, and a "predicted low" near the end, as it burns off. I like it when this happens as I feel like I know what I'm doing. I don't usually eat that many carbs during the day, maybe like 30-45, usually eggs/ veggies/ toast (8G/ slice) in the AM, 1/2 peanut butter sandwich (17G) plus 8G of carbs worth of carrots/broccoli @ lunch and maybe a Greek yogurt for another 7G of carbs. I can run 3 miles on that. If my BG is higher when I start, I skip the milk but I'm usually in the 90s and it goes ok w/ milk and I end up where I started. I've played around with different rates and adjustments but that's what works for me.
Dr. Bernstein is very interesting but is very hardcore. I've lost some weight (peaked @ 275 and am now around 185-90 lbs...) and haven't ever gone to 30G of carbs/ day. I like "Good Calories/Bad Calories" too, along with Taubes' other book, "Why We Get Fat" and they seem to suggest that less carbs can get you there as readily as picking an arbitrary low number. The "history of the science" suggests as many as 75G of carbs can result in weight loss. I eat more than that but maybe I cheat by working out a lot. I don't think 1x tab/ hour will make you gain weight. It's most important to keep your BG ok but I think that if you moderate your diet and exercise to "get healthier" (faster, stronger, more able to enjoy a stroll...) you can lose weight.