No way are the olbs fine. I guarantee you that at some point Clay Matthews and Perry end up hurt...then what? Matthews is a shell of himself so we can't expect him to take over a game so....I say sign Brooks and see what he has in the tank.
You ignored the second half of my post. I said the OLBs will not be fine if injury strikes. As for "taking over a game", I don't expect that out of either of them, but I don't consider it to be necessary if improvements are made in other areas, and I like what I'm seeing from the D-backfield. This doesn't need to be a great defense, and it won't be. It just needs to not have glaring weaknesses in a position group that opponents can pick on whenever they need it.
Frankly, why we would we be concerned about OLB depth more than, say, OT or WR depth needs some explaining. There's a big drop off at those positions as well. And who's the 5th. D-lineman?
Signing Brooks for a couple of mil? Sure, why not, in the overall scheme it's not going to make that much difference. Besides, when Capers tells him pocket contain is Job #1 and spin and swim moves off the snap or other free lancing is prohibited, will he start throwing his helmet?
I don't think many people have observed how the Capers pass rush is supposed to work. Job #1 of the OLB is to not give the QB an escape route. Running around the back of the pocket or taking an inside rush is prohibited unless the play call is scripted to have somebody looping or blitzing the edge. The way this is supposed to work is inside blitzes bring pressure to move the QB off his spot. A step or two throws off the OTs blocking angles creating opportunity to work off the block and come laterally to the inside. OLBs have to play eyes on the QB throughout; the concept is he will have the advantage since the OT has his back to the play. You don't see the OLBs dip and rip very often where eyes are off the QB. When you see Perry do it a few times a year you scratch you head asking, "why not more often?" Well, this is why. The OT's set or some other bit of recognition has to be present to give that move a good probability of success. Try it without a high level of success and you'll find the bench.
You're not going see OLBs "take over a game" in this scheme. Matthews never did. He just had a knack for a handful of flash plays that mattered in his prime. You never saw him whipping some guy inside and outside all day except on some occasion where he was drawing some chump such as a few OT backups we've seen in Green Bay over the years. Any decent player will look like an All Pro on that one day.
Even if you get the inside pressure, or Capers dials up a DB edge blitz with the OLB going inside, this takes time to develop. The whole shebang is designed to get to the QB or get him on the move with the edge covered inside 2.5 seconds. That relies on tight coverage or a look intended to deceive.
No matter how you cut it, Capers' defense hinges on inside pressure and DB and ILB coverage. In a nutshell, Capers is a blitz/man guy; zone coverages without a Pro Bowl backfield becomes an issue.
You could say every sack is supposed to be a coverage sack to one degree or another. That's why they keep piling high picks into the D-backfield. And with Capers preference for high blitz counts, they gotta be man coverage guys. When he has to play high/low coverage all day, every snap, like Gunter low and Dix high against Julio Jones is like playing with 10 guys. You gotta gotta have decent perimeter man corners (and the slot as well these days; see Sanu) if you're going to play a controlled blitz game. Capers was a genius when he had a Woodson-Williams-Collins Pro Bowl backfield. Well, that's a big head start to geniusville for any DC. Genius, to me, is being able to adapt in order to cover a weaknesses. And then we have the "culture of closing" out a game issue.
I have some confidence the defensive picture will improve. While King, and what looks like Hawkins at this moment, on the perimeter I see an upgrade over Gunter/Randall which is where we left off. Young player mistakes? Sure. But I have more confidence these guys can be left alone in man coverage than the previous set. There will better speed at nickel corner, whether that's Randall or a box safety substitute in Burnett or Jones. And just better speed across the board. If Clark keeps doing what he's doing, he's going draw some pass rush double teams opening some blitz lanes.
I don't think Capers is a bad DC. I just don't think he's a good one. He's been stubbornly conservative in adapting. He's years behind the league in working in a gapping 4-3 under into his 3-4 scheme; Clark was drafted with that transition in mind. You can't talk about athletic D-Linemen without giving them the opportunity to use it in gap play.
All in all, I see better coverage personnel, and that might just be good enough.