It doesn't sound as if this diet even considers regular, moderate to very vigorous physical activity for more than 1 hr. (and we know that 1 hr. for some sports can be intense).

So, no fruit at any time?

I agree that sometimes people eat too much for a moderately paced bike ride for 1 hr. that may have only 1 short hill (if that), but for long rides, I find for myself I need to eat something small / sip some water, every 90 min. or so for any ride over 25-30 km. long. Then I can last up to 75 km. before needing a sustantial meal beyond a half a small sandwich.

For instance, last weekend we cycled 77 km. in 4 hrs. on major highway shoulder with cars maxing out beside us, at the speed limit of 110 km. per hr. There were 4-5 hills at 8% with another additional 5 hills at 6%. I conisder that ride in terms of calorie-burning, moderately high with some stress because of high speed cars near us. (And to me mental stress of constant car traffic around, just pumps my adrenaline a tad more.) It was mitigated by 70% of the ride with a tailwind. We were cycling with panniers packed with our own clothing.

It was 30 degrees C dry heat, bright sunlit summer day.

During the ride, I ate fruit, drank water and then at 65 km had an ice cream bar. 1/5 hrs. before the ride I had a breakfast of:

scrambled eggs
1 bagel
2 coffees with milk
1 small glass of fruit juice
2 slices of bacon

Yea, sure I had that (bad) carb. We were at a hotel. I needed that breakfast. We were going to be cycling on route that would have no food outlet along the way for the first 50 km. Out on the prairies...with no trees.

I'm just giving this example that a 4 hr. diet may be a good way to help someone from snacking/eating too much throughout the day. But it is not sustainable for endurance physical activity lasting several consecutive hours.