As a sixth form music student studying Debussy's La Mer, this book has proved absolutely essential. Admittedly, it is quite a heavy read, however the studying of the book has led to my having a much better understanding of the work and of Debussy's musical language.
Howat's study of Debussy's structural techniques, in a geometrical sense seems to add a whole new dimension to music and kicks up questions such as, "did Debussy intend to structure his music in a way that could be divided by Golden Sections, or did it just occur naturally?" or even, "are Debussy's impressions of nature so accurate that they reflect a natural geometry?"
I advise anyone interested in Debussy's music to buy and read this book. It's essential!