Whilst there is a lot of useful and interesting information, you can't rely solely on the guide to get you round. You still need to buy maps (or use a GPS like I did) and there aren't that many recommendations for accommodation. There are also many more pubs on route than are mentioned in the guide, but we stopped at one recommended by the guide and it was great.
In hindsight I think I could have planned the trip (we did the southern loop in a weekend) without the guide but I was glad to have read it for ideas and inspiration.