That is not completely true, but there has been misunderstanding of the ultimate point bshaw was presenting throughout.
What does it have to do with UM? - this comes down to your opinion on the way to construct your roster. You would have no problem with this topic if we were on the topic of say...sub-6'0" linebackers...loading up on "scheme fit" sub-6'0" linebackers, as we have seen, is a poor choice of roster building. If you had the same discussion about small corners, you'd say the same thing. Why? Because those players come with limitations. That isn't to say you don't take any of these guys...but having a roster with a majority of them becomes problematic...as we have seen with linebacker for example.
How does this pertain to college success? As I said in my post...even though the concepts are typically done in areas with high gambling/fantasy influence, that doesn't mean the concepts pertain only to those levels, the questions and conclusions the data presents don't end because one group plays in the NFL and the other plays in college (or high school)...they are still playing the same sport. Which is why its easy to retort with something like "well, look at all these small running backs that are successful in college!"...well, yeah, the sample size is much larger, you're still dealing with outliers. If you had a group on the other end, running backs that were tall and heavy, you'd be able to draw a conclusion that the limitations they have are that they are more likely to fumble, etc. That isn't to say don't take the big boys, but you should be careful to not load up your roster with them or you're more likely to have a team that coughs up the football. If you've got backs that are too "small" you'll struggle on or around the goaline or short yardage situations.
The data shows that the sweet spot for a RB is in the 29 to 31 BMI range. Pretty narrrow. Which is why when I see someone like Deuce Vaughn mentioned in this thread...posters just don't get the concept. He is 5'5" 179 at the combine...very light...but he's got a BMI of 29.8...which falls in line of the sweet spot for a successful running back...these are not the guys - surely - bshaw is talking about.
Also, its not a discussion for what roster construction looks like NOW, but in the future. Chris Johnson is at 5'11" 174 per 247 (he might be bigger, but yall don't really know)...that is a BMI of 24.8, that is just way low. Chris Wheatley has a BMI - per 247 - of 23.7. These are way low...again, no one is saying don't recruit these guys, they are individually, good players...but if you end up with a room with a majority of them...you will have a room with more limitations than you anticipate. Ajay Allen at 25.8. For reference, a 5'11" running back would have to get to 208 to fall in the sweet spot.
My opinion on this...I have zero issues with any of the players in isolation. I like them...especially CWH and Chris Johnson...but I agree with bshaw that we should be careful not to load up on these types of RBs. If you bring them in as complements to add to your offense...all good. But if we end up with a stable of say - 4 of 6 backs in the room - of low BMI (aka small) running backs...I think you'll end up agreeing with bshaw's point retroactively.