My purely anecdotal experience.

I've been on a LC WOE for 5 months now. I started in May of '12 and went whole hog (mmmmm....bacon) and have kept my carb levels in the 20g/day range. I went through the usual setbacks for the first couple of weeks as I adapted to burning fat, rather than glucose. In July I did a 9 day loaded bicycle tour on the Blue Ridge Parkway and Skyline drive (think mountains), giving me 2 months to adapt to this way of eating beforehand.

I did not slack off on the carb level on the ride, and kept the carbs in the same range. As others have said, once you are fat adapted, getting food is not much of an issue. I would eat a big breakfast of eggs, bacon and/or sausage...probably 700 cal. worth, and then snack through the ride. I lived on macadamia nuts and pepperoni on the road, and not as much as you think. Probably 2 oz. of each spread out over 6 hours of riding. I rarely had a lunch, not because I didn't want one, but there were few places to stop. By evening, my energy levels were still high and I would have a typical dinner, not too much at all. If I was camping, I was eating lean rations, as I didn't carry much food at all.

I tour every summer. This was my first LC tour. In previous years, I never lost weight on the ride. the typical mindset on tour is, "eat all you want, you'll burn it off." The reality, in the past, is that you aren't burning as much as you are eating. Not by a long shot. This past summer, I dropped 5# while on tour. I have to think that the ketogenic diet helped me fuel the ride by burning my own body fat, as I ate much less than in previous rides.

This weekend, I'm doing the Seagull Century on the Maryland Eastern Shore. I plan on taking a pocketful of macadamias and some sugar free electrolytes with me, after eating a BAB in the morning.

Goog