Best used as a supplement to the Confraternity of St. James guides. I don't know of another compact guide to the Le Puy to Roncevalles part of the trip to Santiago. It's abbreviations such as L for left, R for right, etc. make it terse and not smooth reading, but it saves on total book size, and weight is important to the Camino walker. This is a 1999 guide, so now getting a little dated.
Once you hit the border of Spain, more recent guides such as Davies and Cole's Walking the Camino de Santiago become available.
On all parts of the Camino, if English is your first language, it is essential to get the corresponding Confraternity of St. James guide books. Do a web search on camino santiago or confraternity, or even backpack45 and they should pop up.