Remember, Lydiard shuffled around his schedule quite a bit from the original "Run to the Top" days till the latest "Running to the Top". Original "Arthur's Boys" were doing hill exercise on an 800m long uphill, 2-mile loop total, with windsprints and fast downhill striding, 6 days a week. He realized (1) not many people could do that much of heavy load (most of them weren't as strong as the original boys) and (2) many just did uphill exercises which was sufficient but there were some missing elements.
Many people complain that they get slower by doing just slow running. Well, they weren't doing just "slow jogging" but certain elements needed to be developed during the hill training phase. Uphill, as most would agree, would develop power in the legs and some technique elements such as high knee lift and back-leg extension. But this is when you should start working on leg speed to overcome muscle viscosity (some may argue scientifically if there's such thing...) and work on the leg-turn over. Some windsprints performed at the bottom of the hill would help but the best way to do it is actually downhill striding. Snell was running an 800m downhill section somewhere around 1:50. Some people fear hurting themselves by doing that and avoid downhill section all together. Some well-known athletes, such as Marty Liquori and John Walker, did avoid downhill for fear of injuring themselves but they could get away with it because they compensated that element.
In most cases, people use shorter hill than 800m (2-mile loop) and Lydiard cautioned doing too much windsprints if the hill is short. Then if people avoid downhill striding and just jog down the hill, which was in most cases, they weren't completely preparing themselves for the next phase: track anaerobic phase. Soooooo... He included what he called "leg-speed" exercise in between hill training days. What it is, as HRE cautioned, is you go out, using slight downhill if possible, always with the wing on your back, never against the wind, run down 100~150m stretch by MOVING YOUR LEGS AS FAST AS POSSIBLE. Don't care about how fast you're actually running. Just concentrate on moving your legs fast. You should take plenty of recovery, at least 300m jog in between, so it won't be highly anaerobic if at all. Also, you should be doing plenty of warm-up and cool-down; if anything, do this after jogging something like 8 miles or so.
I personally recommend you not do this 3 days a week but perhaps twice, even once, a week and do at least one day, if not twice, of long jog of 1:30 instead. Particularly I feel most people don't use long enough hill that aerobic side of maintenance gets a bit short-sighted during this period.
It is Lydiard's fault that he didn't quite fully explain things and when he changed schedule, he really didn't explain why and how he did it; but it's our fault also that we don't really read into what he really meant and just jump into the schedule and schedule only.
Zatopek (I don't think his first name was Emil...) who lives in Osaka, watching the TV coverage of Tokyo marathon, and I, who live in MN checking out several Japanese website links, did an instant coverage of the race last night. It was actually a lot of fun. It's on this message board site somewhere. We'll try to do that for Fukuoka marathon as well.