I am not going to give my opinion on this.  Instead I will use PFF stats.  Let's first take a quick look at how PFF grades.  Their explanation of grading is way too long too post in its entirety so here is the link:

 

http://www.profootballfocus.com/about/grading/

 

Here are some quotes from this link:

 

1. Throughout the course of the season (regular season and playoffs) we grade every single offensive, defensive and special teams snap. We log data such as the point of attack of a running play, the location a pass was thrown and hang time of kicks and punts before moving on to the player-performance analysis.


 

<p style="font-size:12px;color:rgb(0,0,0);font-family:Helvetica, verdana, geneva, sans-serif;">2.There are two main processes that are used to come up with the grades: player participation and the actual grading process. Player participation is more black and white as it consists of which players are on the field, where and general information about the actions they performed (rush the passer, drop into coverage, stay in to pass block, etc).


<p style="font-size:12px;color:rgb(0,0,0);font-family:Helvetica, verdana, geneva, sans-serif;">This process is performed by two separate analysts on two separate spreadsheets. Each spreadsheet is then compared and any discrepancies are reviewed by a third analyst in order to ensure near-100 percent accuracy. We’ve found that both blind runs are generally at least 99.7% accurate and once the games are checked, we’re confident that our work is very close to 100% by mid-week (actually stands at 99.98%).


<p style="font-size:12px;color:rgb(0,0,0);font-family:Helvetica, verdana, geneva, sans-serif;">As for the grading process, it starts as soon as a game is completed. Each play consists of two basic sections, one for the grading and one for stat collection, which would include detail such as (but by no means limited to) which gap the run goes through or which route was thrown on a pass.


<p style="font-size:12px;color:rgb(0,0,0);font-family:Helvetica, verdana, geneva, sans-serif;">The grading for each game passes through three individuals (two who grade every player on every play) to ensure that the grading and stat collection is thoroughly checked and critiqued. This ensures that both our procedures and the interpretation of each play is rigorously checked and consistently applied.


<p style="font-size:12px;color:rgb(0,0,0);font-family:Helvetica, verdana, geneva, sans-serif;">The results:

<p style="font-size:12px;color:rgb(0,0,0);font-family:Helvetica, verdana, geneva, sans-serif;">Cyprien  67th of 84  i.e, 76% of the league' safeties played better.

<p style="font-size:12px;color:rgb(0,0,0);font-family:Helvetica, verdana, geneva, sans-serif;">Joeckle  67th of 88  i.e 79% of the league's tackles played better.

<p style="font-size:12px;color:rgb(0,0,0);font-family:Helvetica, verdana, geneva, sans-serif;">Statistically that makes them pretty much dead even.  How do the stats match up with your perceptions?  Which player, if either, is a cornerstone of the franchise and which is a bust, if either?

<p style="font-size:12px;color:rgb(0,0,0);font-family:Helvetica, verdana, geneva, sans-serif;"> 

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