In the Kelly years we often had very good lines, but almost never lines deeper than 7 or 8.
Maybe we were just lucky, but those guys (always warriors anyway) held up. (playing dinged)
We always had a back-up "interior lineman" (often guard AND center trained), and a back-up tackle.
We rarely had more than 7//8 ready to immediately contribute, and the back-ups rarely played real snaps.
It's "nicer" to have 10//12 ready to go (and I still believe we have that talent); but you CAN go without it.
I don't think I can recall a year where ND lines under Kelly rolled deeper than 5. Seemed like the unit always had that kind of weak link.
The 2013 line was obviously excellent with Martin the Elder, Watts, Martin the Younger and Stanley. But Lombard was kind of just okay. I'd say that any of Absher, Augustine or Jagusah start over him.
The 2015 line was also elite with Stanley, Nelson, Martin and Glinch. Elmer was better than Lombard, but still, not sure I'd take him over Absher, Augustine or Jagusah.
The 2017 line had a crazy good left side tandem of Glinch and Nelson, Mustipher was good too. But that unit also needed a true freshman Rob Hainsey to split reps at RT with Tommy Kraemer, who really wasn't a tackle, and Alex Bars was just solid at RG (shame, because I felt Bars had taken a massive jump in '18 before his injury). Again, I think any of the 3 5-7 guys on this line start on that unit. Hell, I'm not even sure I'd take Mustipher over a healthy Otting.
The 2020 line was probably the closest ND has had to an elite and complete line. You didn't have the sheer highs of the 2015 or 2017 line, but no real weak link in the starting 5. Patterson, Banks and Hainsey were all really good that year, and even Eichenberg and Kraemer being the "weaker" parts of the line were still good. But as we saw, the depth behind it wasn't really there. Correll did well as the backup center, but that was pretty much all he could be. Your next guys in were Dillan Gibbons and Josh Lugg. No disrespect to them, but ND has probably about a half dozen guys on roster right now, who are not projected to start, that I'd say would play over those 2.
You roll into this season with Black, Knapp, Craig, Absher and Lambert as your starting 5, that's probably the most complete starting 5 you've had outside of maybe 2020. But you also have Jagusah, Augustine, Otting, and hell, even guys like Prescod, Terek and younger studs like McKeogh waiting in the wings. This unit has spots where they need to show it on the field, but the talent and depth is better than I can ever remember it being.