I think you're wrong.
Salazar in college.
1977 Alberto Salazar XC training
10 weeks 105 108 110 98 109 106 88 100 98 86 (67 44)
14.2 miles average daily mileage
13.0 miles average long run
15 miles longest run
Alberto Salazars 1977 training summary
70 days, 130 sessions
60 doubles
10 singles
21.5% = percentage of individual runs 10 miles or longer (28 out of 130 efforts averaging 11.85 miles, range 10-15 miles)
14.2 miles = avg daily mileage
69 = number of AM runs (including Sunday long run)
7.1 miles = avg AM run
6.2 miles = avg AM run (not including long run)
61 = number of PM runs
8.3 miles = avg PM run
long runs (13, 11, 13, 14, 14, 13, 15, 12, 12)
13.0 miles = avg long run
15 miles = longest run. One occurrence.
Long runs = 91% of the avg daily mileage
Long runs = 13.1% of the avg weekly mileage