JuCo recruits just aren't realistic options for ND. Hopefully it works out for Smith, but he's a very rare case.
JuCo players fall into one of two categories coming out of HS...non-qualifiers or qualifiers. I don't know if there is any data on % of players in each category, but I'd estimate that 90-95% of division 1 caliber JuCo players are non-qualifiers.
Non-qualifiers must spend a minimum of three semesters (i.e. two seasons) at a JuCo AND graduate before transferring to a 4-year school. They are attending JuCo because they couldn't maintain a 2.0 GPA in "core classes" during HS, had a 2.0 GPA or higher but didn't score very high on SAT/ACT, or, in some cases, didn't take the necessary core classes (i.e. their guidance counselor/school sucks). I think it's safe to say non-qualifiers are not very good academic fits at ND and, even if they could handle it academically, it would be near impossible for them to graduate from ND in the 3 years of eligibility they'd have remaining.
Qualifiers only need one semester at a JuCo before they can transfer to a 4-year school. Unfortunately, division 1 caliber players who qualify academically right out of HS and still choose to attend JuCo are few and far between. Qualifiers are at JuCo because they didn't have any offers coming out of HS (e.g. Aaron Rodgers), had some low-level offers and decided to try and earn a better offer, or, they barely qualified and still weren't accepted into their school of choice (doesn't happen often). I think it's worth letting JuCo coaches know ND is interested in evaluating 1st year/freshmen qualifiers, but I highly doubt it would yield many legitimate options on a year to year basis.
There's a third category of JuCo player and that's one that starts at a 4-year school and transfers to JuCo for whatever reason. They are subject to NCAA transfer rules and must spend at least a calendar year at the JuCo AND graduate from that JuCo. They are very similar to Non-qualifiers, but their credits from the 4-year school may have a better chance of being accepted by ND.
I don't have a problem with ND's policy on not accepting transfer credits from JuCo schools. JuCo classes aren't anywhere near as challenging as I imagine ND's classes are. It may be "academic elitism", but it's completely justified IMO. If I were a ND alum, I'd be proud of the university for considering their classes to be a higher standard than a JuCo. No offense to the JuCo eduation, but ND offers one of the best educations in the world. The gap between ND and JuCo is as wide on the field as it is in the classroom.
Re: RB recruiting, going into 2015 with three scholarship RBs is not smart. We need two in this class.