Soh brothers and Seko were pioneer of ultra-distance training for the marathon in Japan. But the idea is nothing new; Halberg ran 30 miles for training 5000m and so did Norpoth running 60k (I think). This is where Japanese adapted Lydiard principles: as Koide explained to me was "Lydiard trained his runners 100 miles a week so they can sprint the last 200m of an 800m race. We train our marathon runners 200 miles a week so they can run flat-out 5k in the last part of a marathon race." Now it's not a literal description of their training but that's the idea. Seko did 80km training run because he wanted to "feel that 42km is not a long distance." Soh brothers did 125km (actually, Takeshi did 128km), well, for the heck of it. I don't think they ever did it again; nor did they make their runners to do the similar training load once they became coaches. Some of them definitely think they need to put mileages--Fujita is one; I think he did as much as 1200km a month before he did 2:06 but then plagued with series of injureis. Okutani, preparing for Fukuoka last December where he finished 4th in 2:08 to make the WC team, ran 70km a day for 2 weeks. Suwa, who missed the 4th place by a step behind Okutani, preparing for Athens Olympic marathon where he finished 6th, added 10 minutes to warm-up and cool-down and morning jog; total of 30 minutes more running per day. Takahashi runs, for a certain period of time, up to 70km a day for some time. But then again, Noguchi doesn't run as far; neither does Shibui. Ozaki who finished 2nd ahead of Takahashi at Tokyo last year, did 30km runs almost every week but no further. I checked Seko's training and, during his developmental stage where he ran 2:15 behind Rodgers at 77 Fukuoka, was only running about 500km a month and that's not a mega-mileage at all (at his prime, close to 1000km/month). If you can get away with training less mileage fast and run well, go ahead and stick with it. But if you can't, you've got to find a way to perform better and, with the case of most Japanese runners, it is more kilometers. You can go all day looking for runners who perform great with less mileage (Marsh, Doubell, Coe if you want...) but if that system doesn't suit you, you've got to find the way to improve your performance and it could be to run more mileage. There's no way around it. I'm sorry but all the threads about looking for low-mileage performers are, to me, nothing but looking for an excuse not to run more. If you can run 2:08 with that way, all the power to you.