Agreed. I personally think that forcing kids to go JUCO who are close to academically qualifying, but maybe a class or two off, or a standardized test score off, is far too restrictive and pejorative. Especially for the kids who start off poorly, but make a big push at the end and come up just short.
If it is a reasonable amount -- say, 5 classes -- then let them go prep, force them to take that year [instead of being forced into the bottomless pit of JUCO for two full years], and let them make up some of that course work. If they do, then great -- they are eligible if they meet minimum thresholds and achieve a high enough score on the sliding scale.
Why can't the NCAA audit / scrutinize prep school courses with the same level of skepticism that they do with regular high school courses? That will help prevent kids from loading up on a bunch of fake classes, more so that just limiting them to one or nothing.
Just my two cents.