[notacoward]

> Most people who sign up to races are not regular runners

[citation sorely needed]

Yes, some non-regular-runners sign up for a charity 5K, but as I already said that's much less true for a 10K. "Most" is a drastic overstatement.

> In races where most people run

i.e. where most people fit the definition of "well conditioned athlete"

> I expect ~40% of the men to run under 45 minutes

i.e. 45:00 is still below median. Even by your own shifty definitions, you're refuting your own point.