PianoMonk Thanks for sharing your perspective on learning new pieces - very helpful.
It makes sense that someone with your level of experience would view Dr. Gebrian's materials differently than many of us discussing it here. As a professional, I'm sure you've already figured out what works. Imagine you are new(ish) to learning an instrument, or you've never had a teacher, or you've never had a good teacher. In that case maybe this really would seem like a magical formula.
I'm in a Facebook piano group. A retired lady who recently returned to playing asked for help with a difficult section of a piece she was trying to learn. She mentioned that she was frustrated because she had repeated it for 5 hours straight and it just wasn't getting any better. It's not a given that everyone will figure out good practice strategies on their own or will have the benefit of learning this from a teacher (even if it seems like common sense in hindsight). I have been playing clarinet for nearly 40 years but only had 5-6 months of lessons with a pro when I was 18. I've been a piano student for maybe 7 years now and only the last 2.5 have been with an excellent teacher...and still, many of the methods in MG's book are brand new to me. I may only end up adopting a handful of them permanently, but either way I am so grateful for the wakeup call. Just the fact that I am really thinking about how I practice now is a very helpful & needed change for me.