Regarding the Average Usage row near the bottom of the table, I am interested in how much the team used a player when that player actually played.  For example, as to Keke, I ignored the five games he missed.  Strictly speaking, he played 393 snaps out of a possible 1079, which is 36.4% of possible snaps.  However, I have listed him at 50.5% because that is how much he played when he was healthy enough to play at all.  That number is skewed a little low because he suffered a concussion mid-game in week 8 and played just 15% of the possible snaps in that game, but he almost certainly would have played more snaps but for the injury.  Similarly, Whitney Mercilus played 9.92% of possible snaps, but he played a lot of snaps when he was actually in games for the Packer, so 41.5% seems like a more useful number.  The average for the marginal players improved due to playing more than they would have in week 18 while some of the front-line players played less than they would have had the game meant something.

The PFF scores are what they are.  By all means, take them with a grain of salt.  The obvious PFF grade that stands out is the 77.1 grade for Tipa Gileai.  Preston Smith's grade was 80.8, but at no time was Mr. Galeai pushing Preston Smith for snaps.  One more caveat: I believe Mercilus' grade is for the entire year, and not for just his time with the Packers.  

90: Jack Heflin played sparingly in 4 games and was a healthy scratch for the other 13 games.  Apparently the Packers see enough potential in Heflin to protect him on the 53-man roster even though they did not play him very much.  Perhaps the same thing can be said for Vernon Scott and Jake Hanson.  In Heflin's case, Abdullah Anderson from the practice squad received more playing time, perhaps because Anderson had more NFL experience and was more game-ready.

93: TJ Slaton played in all 17 games.  He was up and down.  His best games were probably in week 5 and week 9.  His snap percentages increased towards the end of the year but I am not persuaded that it was due to improved play.

94: Dean Lowry had a good year: he was available and played pretty well usually (not always) when he did play.

95: Tyler Lancaster also provided availability.  He was decent if not exciting when he played.

96: Kingsley Keke sustained some concussions which has been an issue for him as he suffered one at the end of the 2020 season as well.  He was okay as a rookie, and played well in 2020 (at times, very well), but he regressed overall in 2021.  I loved this draft pick when it was made but I was hoping for more from him in 2021.  He will be back in 2022, though I am worried about his concussions and recent "illness" which has caused him to miss several games recently.  

97: Kenny Clark had a solid season.  I do not know why Pro Football Focus does not like him as much as I do.

98: Abdullah Anderson played in 7 games for a total of 116 snaps for Chicago and Minnesota in 2019 and 2020, and added 49 snaps for the Packers in 2021.  He has earned $767,000 in three years and been on 5 teams.  As noted, he has had the benefit of three training camps and some previous experience actually playing the NFL, which is probably why he got the nod over Jack Heflin.

The snap counts for the defensive line were pretty straight forward: Clark and Lowry were the mainstays with Keke, Lancaster and Slaton rotating in.

9: Jaylon Smith came, failed, and was released.

40: Tipa Gileai was not physically ready to play in the NFL last season, and may have more work to do in that regard.  Nevertheless, he battled Jonathan Garvin (#53) for time as the #3 OLB.  Gileai played 152 snaps in 2021.

42: Oren Burks played sparingly in 2021, though he played in every game.  His only significant playing time came when Barnes was out or on a snap count.

44: Ty Summers played in week three because Barnes left the game.  Summers played in week four because Campbell missed that week.  Otherwise, he played only on special teams.

47: Chauncey Rivers received some moderate playing time early in the season before going on the IR for the remainder of the year.

50: Whitney Mercilus provided a need lift to the defense when he was acquired.  He provided consistent pressure as a bull-rusher and decent run defense.  I suspect his PFF grade just for his time in Green Bay is higher than 64.3.

51: Krys Barnes was the unquestioned #2 ILB.  He needs to improve to retain that title.

52: Rashan Gary had an excellent year.

53: Jonathan Garvin played 395 snaps, up from 85 in 2020.  He is big at 6'4" and 257 pounds.  He was a good tackler and had 5 quarterback hits, all of which occurred during the first 7 games. 

54: LaDarius Hamilton was called up from the Practice Squad multiple times.  He ended up playing 64 snaps (5.9%). 

55: ZaDarius Smith played in week one and then was placed on the injured reserve for the remainder of the regular season.

59: DeVondre Campbell was the #1 ILB.  So that's how a good inside linebacker looks.

91: Preston Smith had a very good year.  He injured his oblique in week six after 8 snaps and missed week 7.

The outside linebacker situation also was straight forward.  Rashan Gary and Preston Smith played as many snaps as possible given that they need some breathers from time to time.  Every one else who played did so because someone had to.  I am hopeful that the return of ZaDarius Smith means that we see less of Garvin and Gileai in the playoffs.

The inside was also straight forward.  DeVondre Campbell played every snap he could.  The Packers played Barnes a good bit but mostly by default, as he was better than Ty Summers and Oren Burks.  That was a low bar.

As always, it is time to fess up.  Last March while looking at the salary cap, I suggested releasing Preston Smith and Dean Lowry.  Both ended up playing a lot of snaps and both had quality seasons.  In the case of Preston Smith, the Packers did get a salary cut and a restructure to save $7.25 million on the salary cap.  The Packers did not get a pay cut from Lowry, but the restructure saved almost $2.5 million.  I think writing "oops" is in order.

That being said, while one should never let the accounting be the sole determinant of football operations, I would note that the Packers needed the consent of both players to garner the cap savings they achieved while retaining their services.  Without having contact with the players in question, there is no way to know the terms to which a player will agree and those at which he will balk.