Are you suggesting Gebr had no base behind him? Correct me if I am wrong, but Lydiard base conditioning phase is not THAT slow. "top of one's aerobic capability" reads pretty hard if you ask me, especially on a hilly 22 miler.
Are you suggesting Gebr takes months off of running and comes back doing hilly 22 milers as intervals...
I think the plan for Haile was to take a few days off at the end of the racing season, maybe a couple of weeks I don't know, and then to do a sprint session. The sessionn was 300m 250m 200m 150m I cant remember the times, it was about 10 years ago when I read this, but the 300 was very quick, probably 400m pace, and the 150 was 17 seconds, so that would be flat out.
Doing this session on fresh legs after a break from regular training means that the fitness is still there, but there is no chance of injury and speed comes easily. After this comes the endurance build up of mileage.