So you're saying that the Packer's defense isn't as good against good offenses?? Not to be argumentative but that's true of all but maybe 2-3 defenses in the NFL.
The Giants aren't actually a bad offense but the Packer held them to 221 total yards in week 5.
And here's the kicker...the Packers held the Falcons to their second lowest yardage total of the season; the Packer's defense gave up a grand total of only 5 more yards than the Seahawks (and the Packers were on the road while the Seahawks were at home). I know facts can ruin the narrative and it's really easy to focus on the most recent week and forget the rest of the season, but the Packers defense hasn't been nearly as bad as people want to claim. Now, Capers has been putting together the pass defense with duct tape and bailing wire so perhaps the league has figured out how to exploit a defense that is severely lacking in talent at every level. Now that CM3 is out we can finally see that Perry really isn't anything that offenses need to worry about.
I agree with your premise of doing worse against better competition... Everyone that watched that Atlanta game seen how hurt Julio was. And how easy it was for the Falcons to score when they needed it.
And they have been really really bad the past couple of weeks. Giving up an average of 37 points a game (you can even take the return touchdown out and they are giving up 35). And 4 out of 5... which the sole good showing coming at the hands of the mighty Bears and Matt Barkley.
The Packers are 24th in the league in points allowed against a really weak ... At the end of the day that is the only stat that matters. That is against the 27th, 26th, 17th, 24th, 4th, 31st, 1st, 7th, 8th scoring offenses.
So if you average that it's about 16. Meaning the Packers should have about the 16th best scoring defense. But instead have under-preformed in general and allowed more scoring than average to these teams.