In reply to TobyA:
Haven't got the book a and it's about 20 years since I cycled the route. If you mean the descent from Longstone Edge, that used to be a quarry road with lots of big pot holes. However, there are a couple of possible routes. If you look at OpenStreetmap, the quarry road was the one that is the dotted line next to the Rowland CP legend on the map.