Boo is talking about doing 2 different kinds of weight lifting workouts. #1 is a very heavy, CNS and testosterone building workout- low reps, high intensity. #2 is a circuit training workout, 10 reps, medium weight, several different exercises, no recovery between exercises, 2-3 sets.
Boo’s program is that you do workout #1 on your hard days, and workout #2 on your recovery days.
His theory, as I understand it (I’ve taken 2 of his courses) is that on hard days you should only do hard running and heavy weight workouts, and on recovery days you should only do recovery running and recovery weight workouts- don’t mix the two on the same day.
His program makes sense, and in my experience as a jumps coach it works great, but I do not know how well it works for distance runners.
As for the argument that the intense weight lifting stimulating testosterone and HGH, I have been told that it is more important for women to lift heavy shortly before competition than men, because their testosterone levels drop off more quickly when they are not lifting.