The tone of the article seemed to be low mileage, let kids be kids. But we know that playing soccer at a high level is not just playing around. The guy is super talented and also does work super hard. If a few other talented soccer guys dabbled in track and cross country, they might find similar results. That can be a combination of talent and the fact that they have been working extremely hard in soccer for many years. And kudos to the coach who seems to have found the right balance for this athlete. We have to be careful when we apply this to all hight school runners because most don't play high level soccer.
So if we took a regular high school runner, it might look something like:
Run 40 mpw comfortably, with some tempos, progressions, etc.
Do another hour each day of accelerations, fartleks, surges...
Move ALL directions, work on quick bursts, footwork...
Become a better athlete.