Why the heck are 20 and 30 year old runners who want to break 24:00 (or whatever) in a 5k asking about speed programs when it obviously clear the biggest gains are to be had by running more miles with occasional fartlek type workouts thrown in? Am I out of line saying that almost everyone trying to qualify for their Boston qualifying time should be able to do so with just miles and perhaps one quality workout a week? You don't need to become faster, you need to maximize the aerobic engine to see you will naturally become faster over longer stretches of miles.
Not at all. In addition, the more often one can run high-end aerobic runs the better. But one would not have to pay for some training manual or for some running personal trainer to get that.