You again.
So this again :
1. Before EPO, no Kenyan broke 2:09 for the marathon, and they had no runner in the top 150 all time fastest for either the marathon or half-marathon.
2. What success they had on the track before EPO was due being effectively full-time professional runners in a largely amateur sport, able not only to run full-time, but to compete into their mid thirties (compared to the likes of Bannister and Snell, working or studying full time, and having to retire at their peak by age 25.)
Coe ran 2 seconds faster than Mike Boit.
Ovett trounced Rono at Rono's event while waving to the crowd.
Keino NEVER came close to reproducing his (highly suspicious) performance in Mexico. His fastest sea level 1500m was 3:36.9. Jim Ryun had run 3:31.1 Less than 10 years later and Coe and Ovett were running 3:31.
Before EPO, no Kenyan had broken 3:32.5. That performance (Kirochi) was the 57th best of all time. It took over 19 years for a Kenyan to run (0.03 seconds) faster than Jim Ryun (1986 - Cheryiut).
Before EPO, Brazil had more performances in the top 25 all-time 800m list than Kenya.
Before EPO, only four Kenyans had broken 13:14 for 5000m, and one of those was suspended for evading tests, and another's brother later banned for EPO use.
Before EPO, ZERO Kenyans had broken 2:09 for the marathon, while FOUR Japanese had, THREE Australians, THREE Ethiopians, and TWO Brits had.