Okay, I've been hunting for a Japanese grammar that is organised based on topic, as opposed to the normal alphabetical organisation. So I was excited when I saw this book. Organised based on topics. However, now I would say that the book didn't live up to its promise. It is not a bad book, but I have two worries:
First, the book is uneven. It starts explaining what a noun and a verb is. ("Okay this is a very basic grammar, I guess.") Then it jumps into an historical overview of different verb forms, using terminology from Japanese grammars. ("What? Did I miss anything? Now were into ancient Japanese and in the previous chapter we were told what a verb is? Did I miss something?") I don't mind being told Japanese terminology (actually quite useful), but not as an alternative to English.
Second, the author doesn't seem to know if he wants to write a historical grammar or a modern grammar. For instance: The book include 'wi' and 'we' in the kana. These characters haven't been used in half a century. The book also includes an obscure way of writing very large numbers. These characters are also not used anymore, despite the author stating that the approach is useful for science. It is very easy to add factual knowledge like this and it is much harder to describe more abstract notions in grammar, like syntax. When there is so much focus on factual knowledge I start to worry about the true competence of the author.
Update: Almost immediately after posting the review, do I get negative feedback. Why trash my review rather than write a positive review? I think we can all tell the answer.