I have to agree with you on the bit about the lower divisions of college football.
Sure, there may be a few guys on DIII rosters that are just numbers so the program can hit their quota for enrollment at the college, but if a guy is getting playing time at a DIII school, they were likely a very solid high school player.
Heck, just look here in Ohio to see that DIII guys can get to the NFL. Mount Union has had a number of them, including
Pierre Garcon and
Cecil Shorts. Heidelberg had
Donteea Dye and
Mike Preston. Sure, Bluffton isn't on the same level as Mount Union and Heidelberg year in, year out, but they have some talent as well and had a guy like Ryan Aelker get an invite to the Browns rookie camp in 2015.