The NFL's 4-3 defense goes back more than 60 years, and the 3-4 defense goes back around 35 years, to NT Curly Cup and the Houston Oilers, but neither are the most used NFL defenses any longer. The new dominate NFL defense uses at least 5 DB's or more, and it was used on 52.17% of all defensive plays in the NFL last season. The Broncos even used 5 DB's or more on 57.34% of their defensive plays last season.
The new most used defense in the NFL has become a 3-3-5 or a 4-2-5 (with some virations) without most people even noticing. The "Nickel" CB has now generally become a starter (by number of snaps), replacing either a DT or LB. Maybe that is at least part of the reason the Panthers didn't think they needed to draft another DT this year.
The major reasons for this shift is the use of multiple WR sets (31.4% of all WR yardage in 2011 came from "slot" WR's), and that teams now pass more than run (even the Panthers defense faced more passes 53.6% than runs 46.4%). The Panthers were quick to realize this trend toward 3 and 4 WR sets, by drafting Safties with CB skills (Godfrey and Martin), who could cover these extra WR's one-on-one, but as yet haven't been able to find that 5th DB, a SS who can shift to LB in a 4-3 on running plays. The Falcons have delt with this by trading for CB Asante Samuel, and plan to start him at LCB, with Brent Grimes at RCB, and Dunta Robinson as the "slot" CB.
Football is all about finding and creating mismatches. More teams are now trying to speed up their play calling, by going no huddle once they catch the defense in a mismatch, like a 4-3 defense against a 4 WR set, and then preventing the defense from substituting. That's why the Panthers need to find a big SS, with CB speed, who can also shift to being a small OLB (like Senn, 5-11, 224 pounds), who can play OLB in a 4-3, or SS in a 4-2-5, or a 3-3-5 (with a DE dropping back to OLB). Most drafts only have a couple of such players at most, and the Bears #79 pick this year, CB/S Brandon Hardin (6-2 5/8, 219, 4.36-40) seems perfect for that, remember that Bears MLB Brian Urlacher entered the NFL having played both MLB and SS in college, and could have gone either way in the NFL. The Panthers don't have any player like this now, but they could scan the waiver wire this summer looking for one. The only others in this draft were Sean Richardson (6-2 1/2, 216, 4,47-40), Deshawn Shead (6-1 1/8, 220, 4.51-40), and George Iloka (6-3 5/8, 225, 4.59-40), the only one of these 3 likely to earn a roster spot.
Here are a few veterans that might fit that SS/OLB mold if they're cut.
OLB Wesley Woodyard (6-1, 222, 4.49-40), 5th year, Broncos
S David Barton ( 6-2, 219 now 211, 4.42-40), 4th year, Broncos
FS Michael Greco (6-2 7/8, 224, 4.40-40), 3rd year UDFA, release by Panthers with an injury settlement last year in training camp
LB/S/TE/FB/WR/DE Jameson Konz (6-3 1/2, 234, 4.38-40, 46 inch vertical), Seahawks 7th round pick in 2010, IR in 2010 (hip), and torn ACL in 1st game of 2011
FS Jarmale Hines (6-1 1/8, 219, 4.55-40), 2011 5th round pick cut by Rams, signed by Panthers, and cut
SS Anthony Bratton (6-0 1/8, 213, 4.50-40), 2011 UDFA, Practice Squad player
Here are a few players from the 2013 draft that may fit this SS/OLB model.
SS Kenny Vaccaro (6-1, 215, 4.47-40), Texas, 2nd or 3rd round
SS Ray Ray Armstrong (6-4, 216, 4.54-40), Miami, 2nd or 3rd round pick
FS Baccarri Rambo (6-0, 218, 4.58-40), Georgia, 2nd to 4th round pick
SS DeVonte Holloman (6-2, 232, 4.54-40), South Carolina), 5th or 6th round pick
What Could this mean for the Panthers future?
2012 - It probably means that either Beason (easing him back in) or Anderson will come out on passing downs, replaced by the "Nickel" CB Munnerlyn or Buttler, maybe with a DE dropping back to OLB sometimes.
2013 - It's all on the table. A 3-3-5, taking a DT out, and the "Nickel" CB comes in. A 4-2-5, leaving just Beason and Kuechly to cover sideline to sideline at LB. That would be great if they could find that SS/OLB combo.