John Lynch may be able to take average runners and make them good but so can plenty of other coaches. Chichester at Geneseo is a great example, he was barely under 9:00 as a SO for 3k but look at the year he had in XC this season, just a few months later. Cortland too is a prime example, their only stud runner out of HS was DuBois other than that, Nally and Henry were barely under 10:00 for 2miles, Stermer was running mid-17's for 5k. NYU is another, although they get some heavy talent, one of their best runners this year, Zach Maher was a 17:30ish guy I believe and look at him now.
If we really want to look at it, Heymann was actually better than most all of these guys in HS, as was Ben Jackson. Ben ran 16:53 at the NYS XC champs in '04 but Henry only ran 17:17 in the same race. Same day, Maher ran 16:54, Dubois 16:58, Greenlaw 17:04 and O'Brien 17:14
Its great to talk up your coach or a coach as doing a good job improving mediocre runners, but lets face it, its nothing amazing, especially in D3 where nearly every runner coming in is mediocre at best.