We often see people in the comment section or on social media complain about a lack of sacks from FSU. We saw these comments even in 2013 when FSU had the No. 1 defense in the country. It's a complaint often seen from Alabama fans, too, about Nick Saban's defense. And that should come as no surprise, since FSU and Alabama run very similar defenses.
So here's the deal.
Florida State plays a lot of "match," as Jimbo Fisher calls it. That means pattern match zone coverage, and Nick Saban and Bill Belichek are usually credited with coming up with it while they were coaching the Cleveland browns. Alan Mundy wrote extensively about that here, and you shouldn't read this article any further until you finish his.
In playing patten match zone coverage, defenders are often locked up in what is basically man coverage once receivers declare their routes. That is far different from "spot" zone, where defenders drop to a spot and generally stay there much more rigidly.
Spot zone defenders typically do not play that tight of coverage, but they do get to keep their eyes on the QB a lot more, as opposed to match schemes, which often entail coverage defenders turning their backs to the QB.
Where this really matters is in facing mobile quarterbacks. Mobile QBs are very dangerous against man coverage, because they can eat up yards with their feet scrambling before a coverage defender even realizes the QB has taken off.
FSU's goal is to play very tight, aggressive coverage, and to have the QB get rid of the ball quickly, often before he is ready to do so. Against mobile QBs, the added goal is to keep them in the pocket.
The way FSU accomplishes this is to not have the defensive linemen rush wildly at the QB, opening up big lanes through which the QB can scramble. Instead, FSU's defensive linemen are typically trying to squeeze the pocket, controlling a gap (sometimes two) through which the QB can run, pushing blockers back, making it smaller and giving the QB less room to operate. It's all about the controlled rush, which prevents the unpredictable situation of a QB running around.
Sacks are fun, but depending on the coverage called, and the type of QB being faced, they may not be the No. 1 priority on a play.
Here's Fisher on the topic:
"People say 'you don't rush the passer, you don't get a pass rush.' What they don't realize, is you rush upfield, you give running lanes for the QB. When you match routes down the field in man-to-man like we do in zone coverage and why we get all them interceptions, and you break out, QB runs for 30 yards. You can't say 'go sack the QB and cover everybody on the back end in match the way you match, that doesn't all tie together. Understanding what coverage you're in, rush, other times you'll be in spot zone and you can go rush the QB."
There is no doubt that FSU could get more sacks if it wanted to, but the tradeoff is clearly not worth it to the coaching staff. There's a saying that the worst place to be as a pass rusher is behind the QB. That's doubly true against mobile quarterbacks.