Ironically, Capers wanted to move Raji to a position where he would be single-teamed more and be able to penetrate more (this is more assumption than established, reported fact). It also allowed Pickett to move inside where he was more comfortable. McGinn was the first to catch wind of this switch and reported that the Packers called the defense an Eagle Oakie. It was base 3-4 personnel, but aligned the front five like they were playing a 4-3 under. One OLB was aligned like Sean Jones in Fritz Shumur's defense (7 tech). The other aligned like Wayne Simmons.
It might have been an attempt to stiffen the run D. In 2009 with Pick in the middle, it was a nightmare to run against. In 2010 with Raji in the middle, it was easier.
Now the story conflicts from there. In most base looks, the Packers don't let the lineman Jet upfield, regardless of whether you are a nose tackle or 3 or 5 tech DT. Raji did not fare well there, it was clear Pickett felt more at home at NT than at DE like he was in 2010.
Regardless, the return of Pickett to the middle didn't help the run D. Now it may not have all been about these two. Jenkiins was gone, Jolly was gone, Corey Williams was gone.
But the odd thing about Raji in the middle this year is that there is not much talk about adjustment up front. Trgovac said they might play less 2-gap (he said it was ultimately up to Capers who had not indicated that the calls will change), though he insists that they do not play as much as people assume. And 1 gap doesn't mean you are penetrating up the field like Chris Doleman and Keith Millard either. They were pass rushing first and only playing run D if they saw the ball in a RB's hands.
So I don't think their roles and responsibilities change much. It looks more and more like there will simply be more and different people on the field trying to take away specific things from an offense. Surprisingly, this approach is probably least effective against a San Fran offense, that does multiple things well with similar personnel. It will work better against Seattle unless Percy Harvin can actually play and they find replacements for Rice and Tate.