I recently tried to link three of the long-distance routes in this book together to cycle from Bordeaux to Arles. The first section was great, but the book's assessment of the state of the surfaces was really unreliable! We were supposed to be going along the canal du midi, most of which the book designated 'good quality off-road path' - we got 30 miles outside of toulouse and found the surface deteriorated vastly. For at least 20 miles the path was narrow, rutted, and covered in tree roots, tree stumps, and rocks. My bike is a hybrid and it was ok, althoguh I think for this to have been actively enjoyable you'd need a mountain bike, but my boyfriend has a proper road touring bike and the path was quite impassable for much of the way. We also wasted about an hour just past Sete trying to find a canal path on the Narbonne-Sete canal which was pretty much entirely overgrown and inpassable, and then went back onto that canal path at a later point, on the basis that the book said it was good quality, to find that it was covered in thick salty sea-mud. At this point we gave up on the book entirely and found alternative road routes with the michelin maps.
The book has some good ideas for general itineraries, but if you're on a road bike don't believe what it says about the canal paths being good quality!! And it is not really detailed enough to be your main planning tool on the road.