I knew a guy who was #5 on his team his jr. year in college X-C. He decided to lay it on the line for his senior year; not walk away feeling as if he could have done better. He ran 80-100 mpw that summer in stifling midwest heat and humidity. Came back and was the #1 guy on the team, through Sept. A couple of guys passed him up in Oct., who had much superior talent. He stayed the #3 guy and placed 8th in conference and his team defeated their arch rivals who were ranked #1 at the time in Harrier magazine.
The summer mileage made the difference; no doubt; he didn't have that much natural talent.