For reference: this book is obviously a (praiseworthy) ambition to have a Greek counterpart to the Lingua Latina Per Se Illustrata[1] by Hans Ørberg. Ørberg's way of teaching Latin is, in my view, excellent because it is based on a natural view of learning a language: show something, say what its name is, use its name in simple sentences, work up from there. Each time introducing new words surrounded by already-known…
This works in theory, I guess, but in practice it's just absolutely awful. the Rosetta Stone courses work like this and I spent about 6 months maybe? working through the Korean class. I was only able to form my own sentences because I also bought some grammar books that taught me about particles and the "topic" of a sentence that you put -ga or -i after (depending if it ends in a vowel or consonant) and several other similar concepts.
But also, even pointing at an object or showing pictures didn't work. I remember at one point being shown two pictures and thinking I was being taught "behind" and a word that English doesn't have, for "far behind." Ah, how interesting I thought! Nope, not at all. It was "near" and "far." The only reason I learned this is because I started screenshotting every slide to an actual Korean friend I had and asking for translations of every word (I'm sure I drove him crazy). The reason I stopped doing the class in fact was that he wasn't always awake when I wanted to do the lessons (ironically since he was Korean-American and I was awake in the middle of the night usually lol - if he'd lived in Korea our schedules would've aligned better).
Anyway, after that experience I don't agree with this method at all. Maybe complete immersion does work, because people can correct your misconceptions, but learning from a book without any feedback is a horrible experience.