Most of the things pointed out are common sense, yet the book still manages to draw attention to the basic points to take into consideration for most aspects of language teaching. And the last chapter on misunderstood language points (though quite short) is liquid gold for any English-as-a-foreign-language teacher. Recommendable.
For practical advice on ESL teaching techniques I have read several of Michael Lewis's books. He comes through intelligently and for a individual who has published dozens of books during his life-time and written some lesser known critiques on Heidegger, Lacan and Derrida, it shouldn't be all that surprising. This book however doesn't have the same spark his books on the lexical approach have, so I would suggest you read this in conjunction with those