The charts are a nice graphical representation of why a lot of DI races go out so hard. If one doesn't get out well at the beginning, that's a lot of bodies to fight through later in the race. That's much less frequent in DII and rarer yet in DIII. FWIW, I think it's helpful to the DI runners who are thinking about competing in college while it's something that many of the DII and DIII HS runners might still need to learn when they compete in college. Collegiate XC races tend to go out pretty hard, too. On the flip side, championship level collegiate courses are built to specifications that make it possible to pass anywhere on the course (must be 10m wide the entire way, have a starting funnel that can accommodate at least 600 runners, and no significant turn in the 1st kilometer).
How were conditions for the DII and DIII races at Boardman on Sat? From times for the runners with whom I'm most familiar, my initial guess is that the heat was a factor for many runners. That course is challenging enough in cooler conditions if you overdo it on the 1st loop.
Incidentally, I was told that VASJ's McDonough Invitational was cancelled today due to a maintenance issue at the meet site. I'm told the park where the meet is held (Forest Hills, IIRC) is jointly maintained by Cleveland and East Cleveland. The maintenance in the Cleveland portion of the park allegedly did not happen, so that portion of the course was impassable, and the meet had to be cancelled. I know 1 team affected by the cancellation was able to run elsewhere on Sat. morning. Did anyone else hear about this?
