I haven't read the book, but I did try waiting until my BGs were low to eat some years ago when someone suggested on a thread (not the thread already mentioned here). It didn't work for me, my BGs kept going up and if I exercised to try to bring them down they went up even more.
Since then my lowest BG of the day usually occurs at around 4 pm, but I am not usually hungry until 5 or 6 pm, so I just eat when I am hungry, even though my liver has helped out and my BGs are on the way back up by 5 pm anyway. Since I switched to eating mostly unprocessed low carb foods my hunger levels have dropped so that normally I am happy with one meal a day, plus a snack maybe for hungrier days. I find this much easier, and more natural than testing my BGs to decide when to eat.
I agree with what
@Beating-My-Betes said in post #8, particularly this bit...
"And this idea seems to 'miss the forest, for the trees'. Control of blood-sugar levels would ideally come from a multi-tiered approach, to include adequate sleep, rest, hydration, movement, exercise, getting a 'bit of sun', reduction of screen-time etc. In addition to this, reduction of stress is important, whether it be by spending more time-in-nature and/or cultivating a feeling of gratitude. Assuming a general shift to whole, or minimally-processed foods, getting as many of those non-dietary 'ducks' in a row as possible will provide the kind of (w)holistic support structure for a healthful life."
So many things affect BGs, food is just one of them.