I am more interested in where UM played compared to those averages.
Yards against UM (difference from average):
UVA - 449 (-96)
Pitt. - 587 (+62)
Ala. - 501 (+7)
UNC - 382 (-100.8)
App. - 326 (-138)
MSU - 454 (+21)
NC St. - 421 (+5)
On its face, this doesn't look too bad. We kept UVA, UNC, and UVA well under their season average YPG, let Pitt go off on us a little bit, but kept NC State, MSU, and Alabama to within striking distance of their season average YPG. But these stats include games against far lesser competition.
I'm more interest in what these stats look like when you take out games against FCS (and G5) schools. Generally, I expect most of those offenses' yards per game will come down a ways. For instance, UNC had 540 yards against Western Carolina and 607 yards against Georgia State; NC State put up 525 against USF and 505 against Furman; and Pitt put up 707 against New Hampshire and 598 against UMass (we did a TAD better). I'd also toss App State from the analysis altogether, because they are a G5 team who hasn't played any P5 schools this season besides UM (so it shouldn't shock anyone when their offense has a relatively bad game against Miami).
To me, it looks like two things are true at once: (1) Miami has played mostly statistically strong offenses this season and that has negatively impacted our stats; but (2) we haven't done better than the average P5 team has against these offenses. To me, that indicates that, at best, we're an average (and possibly below average) defense.