I was also surprised that our run D, thought to be good was not when looking at that article. Looking at 2015 stats, we gave up 3.77 yards per carry, 18 rushing TD's, but we're 9th overall. (While having the lowest rush attempts for the season of all FBS 379 against NU for the year). Had teams run more, the opportunities were there IMO.
Throughout the season, I forget who, posted a teams average passes per game and then their percentage against us. IIRC, everyone was higher. Had teams run more against us, our run D might have looked as bad.
I have optimism for the D this year. More depth, complete buy in (understanding of system) and possibly addition by subtraction. I also think Coach P might be that X factor we have been missing.
That's what I've been trying to say for some time. The rushing yards per game stats look better but a lot of that (most/all of that?) was because teams didn't want to or didn't have to even try to run the ball against us.
Eighth in the conference in yards per carry allowed. That's not a great run defense, imo.