> Diet science is chaos.
100%
> What we all need is not another fad diet or fasting strategy or super food, but rather a process that looks like a flowchart so an individual can achieve certain goals.
I really don't think that's going to help. What you are treating as an engineering problem is mostly a human problem. Unless a human is psychologically programmed in a way that isn't counterproductive, few if any processes are going to allow them to improve their health or lose weight on their own.
A lot of times when people "fast", firstly they often aren't actually fasting, but secondly they are often doing so because they see it as a shortcut to gorge their brains out on whatever food they want when the time comes for them to refeed. They may lose some weight, but at a certain point they reach a new set point where they aren't going to see further improvement with the same input, and they're dumbfounded because they didn't take any time to question their original assumptions about losing weight. Giving these people a flow chart probably won't do any good. For a select few, maybe it will.
I've talked to enough people trying to lose weight, and are mystified by hitting plateaus, that I don't think they're going to have the discipline to follow a chart. People get fat not just because of the food but for a variety of psychological issues, and it just so happens those underlying issues manifest in quenching sadness, depression, and anger with addictive junk food. If someone is stuck in victimhood mentality, when they get stuck they'll make excuses to not actually do the hard work of researching, taking measurements, writing down notes, and making adjustments. Instead they'll whine, find excuses to continue eating junk in some capacity, and eventually move on to the next "host" diet fad their pathology can prey upon. It's not uncommon for people to cheat on their diet plan and to not mention it when they inquire with others, only for it to be revealed once too much time has passed. Humans have this strange penchant of being able to lie to themselves as well as others. Try coaching someone who is morbidly obese and there's a good chance you will eventually find out they were having a "cheat day" every other day with a large milkshake.
Those who actually can make a long lasting change need both a reality check and to be honest with themselves. In my opinion, it really doesn't matter that much what particular approach to take with weight loss as long as it involves keeping insulin levels relatively low. Fasting, vegan diet, carnivore, paleo, whatever. Someone who is serious about their weight loss and sheds the victim mentality will be already be able to observe, reflect, and act without a flow chart.
If you are chronically sad, depressed person with low self esteem and learned helplessness, then everything will be a silver-bullet until suddenly it's not, and a cycle of making excuses to break guidelines will just repeat.