I'm tired of the fact free discussions about pass rush/secondary causality. Does a weak pass rush cause a bad secondary or does a weak secondary cause a bad pass rush.

So let's put together some facts. Let's look at:

Teams that added/lost an elite CB

-change in sacks for the team that added the CB

-change in sacks for the team that lost the CB

Obviously this will be imperfect but at least its a start at looking at the relevant data.

I'll do Deion Sanders.

1993 Atlanta Falcons (w/ Deion Sanders): 26 sacks

1994 Atlanta Falcons (w/o Deion Sanders): 32 sacks

1993 SF 49ers (w/o Deion Sanders): 44 sacks

1994 SF 49ers (w/ Deion Sanders): 38 sacks

1994 Dallas Cowboys (w/o Deion Sanders): 47 sacks

1995 Dallas Cowboys (w/ Deion Sanders): 35 sacks

Please think of other examples (e.g. Charles Woodson, Champ Bailey, etc) and post your results in the comments.

the pro football reference 'teams' page is invaluable for this exercise.

http://www.pro-football-reference.com/teams/