With two weeks of training camp behind them, the Buffalo Bills are, to this point, making a solid - if deliberate - transition into the 3-4 defense under the tutelage of coordinator George Edwards. The pre-season looms, so we'll get to see first-hand how effective the scheme can be very soon, but in the meantime, the Bills need to maintain the ability to run 4-3 looks in a pinch should their progress be hindered in any way.
The 3-4 defense requires a nose tackle that plays the zero technique (directly over center) and two defensive ends that play the five technique (outside shoulder of the offensive tackle). Buffalo did a nice job bringing in players to do these things this off-season, including five-technique ends Dwan Edwards and Alex Carrington, as well as zero-technique nose tackle Torell Troup.
But Buffalo has been using four down linemen frequently during training camp, and the plan is to mix in those looks to keep offenses off-balance. That means the Bills will need to employ linemen that can play the one technique (in the A gap, between guard and center) and three technique (outside shoulder of the guard) well. Kyle Williams is particularly proficient with these techniques, as is Spencer Johnson.
Buffalo would be wise to have multiple options in all three areas - five-tech ends, zero-tech nose tackles, and one- or three-tech defensive tackles. Right now, the Bills employ nine defensive linemen, and there's a good chance that as many as seven of them make the final roster.
Nose Tackles (Zero Technique)
Troup, the rookie out of Central Florida, is by far the best zero-technique player on the roster. Lonnie Harvey, a second-year player out of Morgan State, has enough natural power to play the zero as well, though he's still a bit technically raw. Williams has been tabbed as the starting nose tackle for several months, but it's not yet clear how much zero technique he'll be asked to play.
Defensive Tackles (One and Three Techniques)
Williams is the best player in this category thanks to his quickness, motor and instincts. He'll be at his best in sub-package situations when his athleticism won't be as tightly reeled-in. Johnson is a strong three-technique player, and John McCargo is capable of playing either technique, as well. Rashaad Duncan is a best-fit as a defensive tackle as well. Note that most of Buffalo's incumbent defensive line depth resides here, as they were brought in to play these techniques in the previous regime's 4-3.
Defensive Ends (Five Technique)
Edwards doesn't have the prototypical length of a five-technique player, and is really more of a super-strong three-technique that plays the five pretty well. Marcus Stroud and Alex Carrington have the height, power and long arms that most teams love to see with their five technique players; that power and length will help them easily control run lanes at their peak in this defense. Johnson, McCargo and Duncan are all learning the five technique during training camp, but they're not the prototype from a physical standpoint.
How To Build Depth
Buffalo needs to stockpile as much quality depth as they can at the zero and five techniques, as those are the keystone techniques to running an effective 3-4 defense. Edwards, Stroud, Carrington and Troup are all, therefore, mortal locks to make the final roster.
It would be extremely beneficial to the team to keep two natural zero technique players on the roster; as Williams is not a perfect fit there, if Harvey can emerge as a solid backup to Troup at the traditional nose tackle spot, he'd be an excellent addition to the final roster.
Stroud, Edwards, Williams and Carrington are all capable of playing the three technique, while Stroud, Williams and possibly Troup can run the one technique, as well. The Bills inherently have depth at those techniques, but even if we're including Harvey as a member of the final roster, that's still only six defensive linemen - and the Bills are too short on talent to cut a guy like Johnson or McCargo, who have looked competent at the five and are definitely capable of providing depth at the defensive tackle positions.
Buffalo will keep the best 53 players they can find, and if seven of those 53 are defensive linemen, the team will be better off as they attempt to remedy the run defense issues that have plagued them for the past several years. If they keep six, they'll be a bit more strained from a technical aspect, but one thing is certain: if they're only able to keep six players, they'll keep the six that provide them the most technical versatility for their hybrid defense.