Do you need 100 miles per week?

In the 1960's Arthur Lydiard in New Zealand prescribed 100 miles a week for 10 weeks at the start of the training year and athletes all over the world started following this regime. After all Murray Halberg won the 5000 in the Rome Olympics, Barry Magee was third in the marathon and Peter Snell won the 800 and they had all done their 100mpw for 10 weeks followed by hill training, etc. I did 100 mpw in the streets of Clydebank, Dumbarton, Bearsden, Glasgow and wherever else I found myself in the winter of 1964/65. The Derby and County club that won a lot of stuff in England used to have a pack of runners meeting most mornings to get in 10 miles before heading off for work and then trained at night with a long run (ie 2 hours plus) every Sunday. The marathon times were very good off this training mainly because most athletes did their 100 mpw for a short period and mixed it in with repetition training, hill runs, etc. In the 1960's Mike Ryan, a Scot from Stirling who had emigrated to NZ, trained three times a day before winning the national cross country title in 1967. In Scotland many runners running under 2:20 were regular 100+ men. Colin Youngson says that he could not handle 100+ and limited himself to 80 miles a week which he could handle. He had 40 marathons under 2:30 and nine sub 2:20. Don McGregor had 24 under 2:20 with the last one being at the age of 46 and Fraser Clyne had 22 sub 2:20 marks. Any seminar or course or training weekend for marathon runners concentrated on how to do the best time and the top guys would share their secrets. Almost all had big miles attached.
Then the era of the mass marathon came along and the training schedules in the 'Observer' by Chris Brasher and John Bryant were aimed largely at helping people engineer their way round the distance in four, five or six hours. Nothing wrong with that at all, entirely praiseworthy for people for whom athletics was a hobby or something they did for charity or who were only aiming to do the one marathon to prove they could do it. I had a group fo six ladies from Balloch who only wanted to run the race and finish it. They did and the last one was timed at over 6 hours - but then she had arthritis and had problems apart from running.
BUT
The notion that you could do a marathon without doing the miles was seized on by many club runners and the phrase 'train smarter, not harder' came into vogue. The two should not be in opposition - why not train harder and also train harder than you are doing? The mileage was thrown out with the mass marathon. In one marathon I remember thf irst Clydesdale doing 45 mpw was fourth in 2:41, the second on 60 mpw was next in 2:45 and the third on 100 mpw was outside 3 hours! The two did not cut their miles to 45!!! All three were training seven days a week and racing almost every Saturday and had years of had training done.
Don't assume that big miles are junk miles. Find the distance total that suits you and remember you won't find out what suits you by not trying bug miles, you won't find out what suits you by not trying rep training on the grass or on the track. You are your own coach no matter who you are working with - while the coach knows a lot about running, you are the expert on yourself! Every runner is an experiment of one but you can see further by standing on the shoulders of the more experienced.