This is another “someday” book that sat on the shelf for many years that I decided to make time for. Been going through it, slowly, over the past year or so. Each exercise runs through all keys and usually has at least 20 rhythmic variations to do. Usually I will run through one position on the guitar for each rhythm pattern. Takes quite a while to complete just one of these exercises. Right now, I’m about two-thirds of the way through and happy that I made the effort.