How much of a difference does optimal training make, as compared with hobby jogger training?

I can't speak for any track related training things. I am a ultrarunner.

But generally speaking I think going "professional" is not the recipe for success. Nowadays I think it can be quite the opposite.

20-30 years ago most runners even on top level had a job. And I think most of the Europeans still do. Great examples are Jim Walmsley (Flagstaff) and Francois D’hane. Jim is a professional runner and Francois has a full time job.

Jim has too much time on his hands and runs himself into the ground while Francois has a job and trains when he can. The Japanese 100k World Champion who beat Jim at the Hoka 100k has a full time job as well.

One problem is, I think that "professional" runners think they have to train/win something all the time and post it on social media.

Having a job is not ideal for training but I think you can do really well if you use your available time right.

I know I've done that in reverse. When I graduated I stopped training hard. After a few years of consistent but aimlessly running, I'd slowed roughly from the first times to the second.

1. Why would you bother sweating for 30 mins 5–6x a week?

2. Why would you bother training full time to run an above average high school time.?

3. Just go an extra 15-20 mins and you could hit 40 MPW and hire a coach at sea level.