No I'm am not a doctor.
I don't see where it was misleading, the body at all times is undergoing muscle gain and loss. The NET difference or AUC is whether we actually gain more muscle or not.
I think you're missing the point. Nowhere did I say it necessarily had any added benefits over a more moderate deficit but that would depend on the context of the situation. Your sole focus of avoiding this type of diet (PSMF) is bc of muscle loss. I am telling you EVERY diet will make you lose LBM. That is unavoidable. But the amount of actual muscle loss isn't solely dependent upon caloric intake, in fact caloric intake isn't even the number one factor for muscle loss.
To understand why priming MAY benefit you you have to understand the body's ability to adapt and respond to a stressor. This is how weight training works. Provide an adequate stressor (lifting weights), get sufficient rest (recovery), and the body will adapt to the stress so once exposed in the future to the same stress it responds easier. Same principles can apply to dieting and why diets such as IF and Warrior Diet have had tremendous success (when following other basic nutrition principles). The catabolic response to fasting or periods of low caloric intake is matched and sometimes superseded by the body's compensatory effect. Here's one study showing this effect:
Increased p70s6k phosphorylation during intake of a protein–carbohydrate drink following resistance exercise in the fasted state - Springer
Now to your argument of muscle loss or catabolism. Again, the body is constantly fluxing between muscle building and wasting. The reason we get bigger and stronger is bc the muscle building happens to be greater than muscle wasting...not bc we can completely stop muscle wasting. Your argument that such a drastic caloric intake will lead to muscle loss is not accurate bc of what I said above (you'll always experience some muscle loss) and bc caloric intake is not what determines muscle gain or loss. The body's first source of fuel is carbohydrates to be turned to glucose. This diet (almost all calories are protein) will only include trace carbs so they're not going to be a source of energy here).
The other options for energy are fatty acids (which I'm sure no one would mind) and protein. Protein can be converted to glucose via gluconeogenesis. If not enough protein is provided in the diet then yes the body will take it from muscle and organ tissue (catabolism). But remember, most people on this diet will be getting 1.25-2.0g/lb BW of protein. This is MORE than enough to provide sufficient glucose and prevent the body from releasing stored protein from muscle and organs or go NET catabolic. You see, protein intake is set high enough to prevent the muscle loss you're so worried about in the first place.
Lastly, EVEN IF you were correct, and catabolism was an issue, how much muscle mass do you seriously expect to lose in a few weeks? This is a SHORT TERM dieting plan. Not a long term one. OP mentions running this diet for 2wks. Only a minuscule amount of muscle mass will be lost during those two weeks and the differences between that. And your. 20-25% reduction is NEGLIGIBLE. If planning on running it longer the diet has built in refeeds to prevent adaptation down-regulation of metabolic hormones like leptin, ghrelin, T3/4, peptide YY, etc.
Once again I'm not saying this is better or worse than anything else. It may or may not work better for OP. Most ppl cannot mentally handle such a diet so kudos to him if he can. My point in this is to point out that catabolism is not a viable concern for not running this program since it will be minimized as much as possible as with any other type of diet.