1. the (comparitively minor) cons:
The idea that you need to "undereat", or eat at all during the day, is totally BS. In this sense, this diet is far inferior to the OMAD diet, in the sense that constant snacks during the day breaks your fast and kicks you out of ketosis. Who ever has tried intermittent fasting knows that if you can manage doing any kind of short fast, eating small snacks is just counter-intuitive.
Also, the choice of snacks is also questionable. Although the food choice in this book is laughable from a carnivourous perspetive, the consuption of large amount of fruits would be frowned upon by any health gurus (at least those with their brains lol.)
2. the pros:
This might be the first and only serious book on the OMAD diet, at least within the recent twenty years, a book with some biological and evolutional, or maybe even philosophical reasons as to why this diet is optimal for health. The author's other book gets into the technical details of how hormones interact on a biology level, which is almost unprecedented in popular diet books.
It also proposes the hypothese, that "human metabolism is not reflected in calories per day, but calories per meal." Of course he doesn't have any proof for this claim, but this is one of those things that reshape your view towards diet and health, and you can testify it using your N=1 experiment. If this is true, then squeezing all your calories into one meal not only doesn't lower, but actually increases your metabolism.
Among other intermittent fasting plans, which only pay attention to the length of eating window but not the actual schedule of eating those meals, this book does itself justice by specifying the time of the one meal of the day --- at evening. In other words, the book not only pays attention to the absolute time of fasting, but also potentially its relationship with the circadian rythm and one's duties during the working hours in this modern life where battles are not fought in battlefield but workplaces.
A nice little jewel is its reference to historical patterns of (poor) people on a vegetarian diet who feeds all day, and (rich) people who can afford meat, who only eats one meal a day. Even though not pointed out by the author, this gives some empirical evidence to how the actual food affects one's ability of transitioning into ketosis.
Another little jewel is the observation that "you should stop eating when you feel more thirsty than hungry." For all raw carnivore, it is well known that thirst is not indicator for water deficiency, but a signal for fat deficiency. I believe his recommendation is based on the (subconcious) concern about not eating enough fat, as seen in any of his sample meals, although he may not be aware of it.
3. personal experiment
Like said before, intermittent fasting with a 16/8 schedule is already powerful in weight loss, in the sense that I am losing ~ 1 lbs every week on a very high calory diet. However, the pitfall of eating two meals a day, is that people usually feel shitty after their breakfast. I have progressed to a point where I have to take a nap after my noon "breakfast" and it was annoying. I was so ready to upgrade to OMAD knowing that I can sleep right after my only meal.
Just like no carb or raw carnivore, I had a lot of concerns before experimenting, and read all the literature I could find about its danger and benefit. After doing it for a while it was like "duh, this is the most natural thing to do and why isn't everyone doing it."
Plus, eating three meals a day probably has taken a larger toll on my health, compared to carb eating. If there was any health debt I need to pay for, this might be a large part of it in addition to eating cooked food.
(to be continued)