In ND's 3 losses (all to Top 50 rush defenses) in 2017, ND rushed 37 times for 55 yds against Georgia at home (1.5 yds/rush); rushed for 109 yds on 36 carries vs Miami (3 yds/r); and rushed for 154 yds on 44 attempts against Stanford (3.5 yds/r): 308 yds on 117 attemps (2.7 yds/r) and that was with Nelson, McGlinchey, Adams and Wimbush running a lot of zone option -- not to mention the huge chunks Wimbush often got from QB scrambles -- rather than the RPO, as a running game staple.
If your an offensive staff and your goal is to get explosive (chunk) plays and you don't have RBs who can get them between the tackles and don't have the speed to get outside (it was painful watching the ND offense trying to run outside with Jones at Michigan; why they even tried I have no clue since they usually rely on jet sweeps to try to get explosive plays outside in the running game), then what are you going to spend your time practicing?
I don't blame the OL for the false starts at Georgia. Take those away and it's not good but it's not a great problem.