There was more fast running in van Aaken's system than many understood, partly, I believe because van Aaken presented what he did in a way that emphasized slow running. For example, he described a workout of Norpoth's that consisted of 10x400 in 2 minutes each, followed by 2km at a minute slower than his best time, followed by another 10x400, another 2km until Norptoth had run 15-17kms.
It sounds slow, but the 400s were really 350s done with a 50 meter walk. That means the 350s were done in one minute.
No, it doesn't. I've done 20km runs on the track going 350 run/50 walk as Van Aaken suggests. It takes me 25-30 seconds to walk the 50m interval regardless of how fast the 350 goes. Going 2 minutes per 400 means you run the 350 in 90-95 seconds, which translates to around 1:45 for 400m (7 min/mile, 3:45/km pace). Van Aaken wasn't running 69 pace for 350 and then taking a minute to walk 50m. Try walking 50m in a minute sometime, it's like the speed you move standing in a slowly-moving line.
I've found a straight 350/50 run (that is, no breaks to run fast 2km repeats sprinkled in) to be a good indicator recovery run. If I'm truly tired, I stay stuck at the same pace for the 350s, but if I'm feeling at all recovered from prior efforts, the 350s start to get faster as the run progresses w/o even trying. I did 13 miles on the track once where I was running the 350s in just over 90 seconds at the start, feeling stiff and heavy-legged. By the end the 350s were taking just over a minute and felt smooth and relaxed. The last two miles, with a walking break every lap, went in 12:20, and it felt much easier than 6:10 pace at the end of a 13 miler would normally feel. The 350/50 recovery run offers its own feedback in a way that ordinary runs often don't. If you're struggling to get through workouts and feeling flat or stale in general, I recommend it highly. You'll get strange looks from the other people using the track but who cares.
Some of what Van Aaken says in his book, about eating 1,000 calories a day and sleeping only 5 hours while running 4-5 times, is pure sci-fi. Despite this, the core message of more easy aerobic running improving your running is a good one. He offers an antidote to the endless miles of hammering that fry so many people. It's easy to see why Pre, patron saint of all hammerheads, didn't like Norpoth--they viewed training from completely different perspectives. Which one got an Olympic medal?