But in 2010, the run defense slipped. Some of that was by design, as Capers often called for only two defensive lineman to sacrifice some run support for pass coverage. Also to me it seemed like they were bring 4 guys more often than last year and counting on the coverage more than the blitz than last year.
The Packers aren't going to switch back to a 4-3 because they don't have the personnel to do it, and Capers is a 3-4 defensive coordinator who probably isn't as effective in another alignment.
I wouldn't count on that, other teams like the Bears and Eagles have commented on how the 2-4 is more like playing against a 4-3 than a 3-4 as the OLB get close to the line of scrimmage.
Also Capers did put the defense in a 4-3 look with the 2-4 nickel personal for at least one drive. The two OLBers dropped down close to the line of scrimmage and Collins moved up to the LB level, leaving Burnett as the only guy deep and they had 3 CB in the game.
I can't remember which game it was but I do remember Poppinga playing in the package, one play he did very well and another play he got pushed back very far by the OT and Collins got pushed back by the TE but finally got off the block.
But I think a great thing about Capers is he tries to form the system and plays around the players he has, not tell the players to form around the system and plays he has... as well as Capers willingness to mix it up... which confuses QBs if the players pull it off right.