I've been rereading a lot of the coverage from around the time of the announced switch to the 3-4 and I've been reminded of a nagging question I had at the time that has still not been answered.

Who, exactly, does McCarthy expect to do the heavy lifting on defense?

Here's how Bob McGinn reported McCarthy's thoughts on Cullen Jenkins' responsibilities:

Unlike New England and Miami, the Packers will not ask their linemen to two-gap. Instead of playing head-up on an offensive lineman and being responsible for the gap on either side, the defensive linemen generally will play to the edge of blockers.

"We'll be more like Pittsburgh and Dallas," McCarthy said. "I'm not going to make Cullen Jenkins stand in there all day and play two-gap. Would you make Cullen Jenkins do that? No. Of course not."

This is shortly followed by:

One of the inside linebackers will be labeled the strong side and the other will be the weak side. Unlike the traditional 3-4 fronts of the past and currently in New England and Miami, the inside linebackers will be somewhat protected. 

"Do you want guards up on your 'backers?" McCarthy said. "Probably not. So you've got to play a technique (up front) to let those guys run..."

Now, maybe I'm reading too much into this or maybe I'm just a football idiot (don't answer that) but if you're not asking your linemen to play two-gap, who exactly is going to be protecting the inside backers? You can't have your cake and eat it too. If I didn't know any better, I would think McCarthy is trying to make it seem like nobody is going to have to do the grunt work here. We know that's not true. If, as he says, the Packers aren't going to play two-gap on the line, how in the hell do they protect the inside backers, especially an already-light-for-the-position Nick Barnett? He and Hawk have shown limited ability to get off blocks as it is. 

If there are any coaches out there who could illuminate me on anything I'm missing here, I'd love to hear it.