Been a bit of talk of the NCAA region at Huntsville justifying the course length. I went back and compared Regional Times vs. NCAA times for the Men's 10k. Most regions had 20-30 runners run both at Regionals and Nationals, eliminating any outliers, here are the average time differences:
(+ values = faster Regional course, - values = slower Regional course)
Waco -0:46
Iowa City -0:46
Provo -0:25
Franklin Park -0:15
Lehigh -0:05
Huntsville +0:11
Sacramento +0:11
Angel Mounds +0:16
Louisville +0:22
This doesn't make any conclusion for the HS race other than showing the course ran fast. I doubt the course is short, but it's definitely faster than most on these small samples.