I can't believe he left off the Reg Park variation! this one calls for 60% x5 80%x5 100%x5 , 5 , 5 (the percentage of the first two sets being based on the planned weight for the last 3). If you got 5 on all the sets you added weight, if you didn't get at least 12 reps total on the top 3 sets the weight was too heavy. It's a good system, basically the same one recommended in John McCallum's Keys to progress.