This is great thread. As someone that uses the Daniels' book as the guide for all my marathon training, I will say that there are a number of typos in the 2nd edition and the brief descriptions he gives for some workouts leaves me guessing about pace. He states that for tempo runs that are longer than 20 minutes you should slow the pace down based on a chart provided in the book. However, I have never been clear what pace I should run the tempo workouts like the one we are discussing here. I have always run them as if they are less than a 20 minute tempo (at the fastest pace) since there is rest between each set. However, I recently tried to do a workout similar to this one at the fastest tempo pace and came no where near completing it at the right pace. I am at the peak of my marathon training. It lead me to wonder if I should have been running at a slower pace.