Sprinters running a mile...
Unless I missed it, one has to take into account that in a decathlon the
1500 comes at the end when the athletes are spent after 2 days and
perhaps 16 hours on the scene.
Surely, if a decathlete decided to run only a 1500 meter race, his time
(regardless of his decathlon PR would improve anywhere from 5-15 seconds
When they run the 100 meters, they are fresh and their times are close
to their optimal potential. Not so in the 1500.