Even this year, Southern Cal and Virginia Tech were only middling, and ND only squeaked by both of them. In 2018, Ball State, Vandy, Pitt, and Southern Cal were pretty weak, and ND beat each by 8 points or less.
In 2017, when the latest coat of paint was still wet, ND had several lopsided wins, but sandwiched between the humiliating losses at Miami and Stanford was a harrowing come-from-behind home win against a Navy team that only managed a 7-6 record.
Wins over a superior opponent are a species that has not been spotted anywhere near ND's team since at least 2012-2013, and not in a season without vacated wins since Holtz.
To your point on Southern Cal, didn't we only beat them