Like I said, they were missing 3 starters for USC, not 7 or 8. They'll be better, I don't think they'll be anywhere close to great.
Hmmm....our counting must be a bit different
Defensive Players missing for USC:
Starters
NT -- Jarron Jones (2014 Starter)
DT -- Sheldon Day (2013 & 2014 Starter)
WDE -- Ishaq Williams (named Starter prior to 2014 season before being suspended)
MLB -- Jarrett Grace (2013 Starter, leading tackler when healthy, missed all of 2014)
MLB -- Joe Schmidt (2014 Starter, voted Defensive MVP)
CB -- KeiVarie Russell (2012, 2013 & 2015 Starter, named starter for 2014 before being suspensed)
CB -- Cody Riggs (2014 Starter)
FS -- Collinsworth (2013 & 2014 Starter)
2-Deep
NT -- Daniel Cage
DT -- Tony Springman
DT -- Jay Hayes
ILB -- Greer Martini
S -- Nicky Baratti
By my count, ND was missing 8 Starting Defenders it was counting on....but even the most "conservative" number of missing Defensive Starters would be 5-6, with a majority of the 2-Deep then missing
Trying to say they were missing "just a few" defenders for the later part of the season is just plain inaccurate......it simply wasn't even close to the same defense (personnel wise) as the earlier part of the season
Notre Dame will undoubtably be better defense after only losing 1-2 defensive starters from 2014, and adding in 2-3 Starters from Injury/Suspension that didn't get to play a snap in 2014 (even during the early part of the season)....not to mention the 5+ additional starters they'll get back from injury.....plus all the 2-Deep players they get back from injury......plus the fact that basically the entire defense is a year older.....plus the fact that they'll be in Year 2 of the new scheme/DC
I wouldn't rule it out from being a top level defense, as it will have the NFL talent necessary to be at that good at every level of the defense.
Day(DT), Jones(NT), Rochell (DE/DT), Jaylon (ILB/OLB), Russell (CB), Luke (CB), Redfield (FS), Shumate (SS) are all projected to be NFL Draft Picks in either the 2016 or 2017 drafts....and some project players beyond them too
The defense Texas will faces will be a RADICALLY DIFFERENT defense than what USC faced....if for no other reason that it will have 5-8 starters back and a boat-load of experience beyond that