Thank you for the ideas! What I'll certainly do is read prefaces.
I like Goeff's way of weighing a book: will it be useful when nothing else helps? Well, this is a book for beginners, so the question is, Why start with this insted of something else. I think I have some arguments:
1. I live in Romania, where very few greek textbooks are available (about 3, I think. Comunist hed little interest in humanities...
2. The first lesson, that about phonetics, isn't a summary, a short account, like in other books: it explains every feature, giving examples which are also analysed. (e.g. when explaining accents)
3. I haven't made up any texts: every sentence is selected from a well-konwn author. They are simple statements, which can stand alone (kind of mottos)
4. All redundant information has been eliminated. (At least I hope so..)I have only explained grammar that is needed for understanding the sentences. (When you are just a beginner, you don't read long texts, where the passive or pluperfect are used; you are confunted with present, aorist and accusativus cum infinitivo. So I found it much more useful to teach the infinitive than the perfect.)
5. In other books, you are given the grammar and the vocabulary, then the texts. You either understand them or not. I give precise rules of translation, which can be used when the text is not clear. The student gets used to irregular word order in his early stages.
6. The book also offers information on Greek culture: tragedy, philosophy, mythology, ancient science and Weltanschauung etc.
7. Finally, it doesn't impose a specific style of learning. When you're finished, you may start studying any other reader or writer.
I'm looking forward to reading your opinions!