what separates the winning championships from 4th places is something I've always been obsessed with.
I think the greats have two opposing dualities: 1) They are type-A obsessives who follow a plan and are willing to train WAY to hard and 2) they are willing to chill out and not follow the plan at a moments notice.
^^^The person that has these dualing personality traits is a special person; not many people are simultaneously obsessive and chill.
Elite running is littered with the skeletons of training try-hards. Everyone wants it and most people train too hard.
One of my favorite anecdotes is that the greatest american XC skier of all time Jessie Diggins has stopped training with a heart rate monitor. She does all her workouts by feel; which almost no other athlete does. And the reason she stopped using her HR monitor was because she felt she was obssessing over then numbers and it was getting in the way of her feeling. She had the confidence to acknowledge her obsessive type-A nature and made a proactive plan to deal with it. (She also has a 15 year coach that she has an amazing relationship; one of his primary tasks as a coach is telling her to hold back)
How many elite runners do you know that would be willing to turn off their GPS watch or stop taking splits in their interval workouts? Not many. But counter-intuitively, chilling out with training is probably the #1 thing a type-A elite athlete could do to improve.