imagine you have 100 runners:They all run 30-40 miles a week.
They are all at +/- 9% bf. We now do a track test with them.And they are all all worth 5:00 - 5:20 for 4 laps round the track.
Now we split them in 2 groups.
g1 are the runners who are asked to run 60-70 miles per week.
THis group is asked to keep their current pace though: 7 - 8 MINUTES PER MILE.
g2 they are running with a clock around the track.They need to run 60 seconds slower then their 1600 meter time per 4 laps.After 2 months they need to run slightly faster 50 seconds slwoer.2 months after only 40 seconds slower. Then their is a test on this group. Then they repeat the 1st cycle with the new times.
Now we take both groups after 2 years wich group would win?
------
Lets imagine they where all craig mottram's. What time would you think they'd run on the mile after such a 20 mintue run a day. do you think theyd close in at 4:10 for 1600 meters ?
So be close to 20-30 seconds per mile from top shape?
Say an average human can run 4:20(65s/lap) in top shape.
Wouldnt this get him at +/- 4:45?(so when they hit final plateau they'd all be running at 5:25/mile on their training runs).
Personally everything training needs is there.Its not optimal i'm not saying it is.But wouldnt you get teams pretty far using such an approach. After all its a progressive training where you look and see how you're body adapts.
It would lso seem a good base for further training without going wrong: f.e. by slowly add 5 minutes a day ever 2 months or so? Till they run this pace one hour.And then add some speed days.