The major benefit of this defense has been rendered obsolete now that there are three teams using it. When Seattle first started using it, they were able to acquire the foundation of their defense using cheap free agency and the late rounds of the draft, because they were players that weren't great fits in traditional defenses. 

 

They were able to sign Browner off the street and pick up Sherman as a 5th rounder because tall slowish corners weren't thought to be agile enough for traditional defenses.

 

Red Bryant, Alan Branch, and Chris Clemons were all journeyman "meh" players signed for cheap because they weren't great fits in a 4-3 or 3-4.

 

Kam Chancellor was a 4th or 5th round pick because cover 2 teams didn't want him because he was too big and slow.

 

This approached allowed them to use their higher draft picks on players that other teams would compete with them for, such as Earl Thomas, Russell Okung, and Bobby Wagner.

 

 

Now that these types of players have been proven useful, and two other teams are competing for these types of players, this defense doesn't have the same benefits.

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