Many people on here are very familiar with Jack Daniels book and his training methodology. I have trained under his method for my entire running career (11 years), and have seen a steady progression and good results. I have a few discussion points that I would like to bring up and see what other, likely more knowledgeable, runners and coaches have to say about it, specifically the 5k/10k plan. Feel free to respond to any or all of the topics.
1. Jack's plan spends 6 weeks building a "pure base" of easy runs, and then spends the next 18 weeks doing workouts. For an experienced runner with many thousands of miles in their legs, is 6 weeks enough time spent strictly building up mileage? He suggests continuing to build mileage through phase II, which would give 12 weeks of mileage building before stabilizing throughout phases III and IV.
2. Kind of as a segue from my previous topic, Jack recommends starting working on speed in the form of R workouts pretty early on in the 24 week training plan - starting in week 7. From reading posts from Renato Canova on these boards, it seems many elites are working on speed nearly year round, so perhaps Jack was on to something here. Is there such a thing as too early for real speed workouts? Or should it be kept strictly to strides?
3. For much of phases II and III, and for one of the two variations of phase IV, Jack Daniels schedules 3 workouts per week, often 1 T workout, 1 R workout, and 1 I workout. I have seen many post collegiate groups and college teams stick to 2 workouts per week instead (my high school team did 3 per week). Is 3 workouts per week too much? Or does that come down to the individual runner? For much of phase II, the R workout is much like glorified strides, and the I workout is usually in the form of a fartlek, so neither are too stressful, and additionally phase II alternates weeks of 2 and 3 workouts. Phase III, which Jack says is supposed to be the hardest, has relatively intense I workouts alongside R and T workouts, and also has 3 workouts each week.
Feel free to respond to any of the above, or to bring up additional topics related to Daniels' 5k/10k training plan.