Really useful in planning a month of hiking in the Spanish Pyrenees and Andorra. I was less concerned with the French pages as I can't take the dog there...
The main thing you want from a book like this is a ranked list of the best hikes, perhaps catagorized by difficulty and taste (climbs, views, waterfalls, etc.). Instead the book is an encyclopedia of trails, all of which are described with exuberant superlatives ("bewitching beauty" and the like). Perhaps this is useful for an expert who's already been here several times and wants to discover new trails. But for people visiting the Pyrenees for the first time (and not planning to stay for months), the information overload makes the book's utility limited.