People expect more form this team because this team has set the standard. Why would you think people would demand less of them than we've seen them demonstrate in flashes? Do you think the coaches look at them and say "Perfect. No need to practice anything."?
Now you're preaching to the choir. This secondary would get killed if it was left alone in a blitzing man-to-man system all game long. But that's not where you've been focusing your commentary, at least with regards to what I was responding to.
This team's defense is not making big plays as consistently as you seem to imply. That's the problem. That's why it can't maintain big leads once teams air it out late, and that's why it can't stop opponents from marching up and down the field against it during the course of the game. The "bend but don't break" concept, as many term this style of defense, has been getting roasted through the air like never before in Belichick's tenure. Given the way teams attack the Patriots, and the opponents the team has faced, it's not really surprising that the team is near the top of the league in interceptions, and down near the bottom of the league in forced fumbles, is it? The following list is from NFL.com, and is obviously going to add more compiled stats to the Patriots since they've played one more game than most teams, but:
No team has been passed against more.
No team is allowing a higher completion percentage (68.3%).
No team has surrendered more passing yards.
No team has allowed more first downs.
They are the 8th worst team in the league in yards per attempt against.
They are 2nd worst in the league in passing yards allowed per game.
They are 3rd worst in the league in passing players of 20+ yards against.
They are 9th worst in the league in points allowed.
There's plenty to talk about, plenty to critique, and plenty to be concerned about, when it comes to analyzing the defense. You claim that this defense doesn't stink at all. Clearly, the above shows that your claim is not beyond argument.
This defense has Wilfork, Mayo, Meriweather/Sanders and, arguably, McCourty. After that, it's all duct tape and chewing gum right now. One linebacker can play only the run, while another can play only the pass. One d-lineman can stop the run, but couldn't pressure the QB if he had a rocket strapped to his ass, while another can get to the QB, but can't hold up worth a damn against the run. Come playoff time, those higher level teams will likely be able to exploit that, through scheme or talent, if that group doesn't get significantly better. Teams being able to gash the Patriots run defense by running against sub packages is just one example of what's to come in the future if the team's talent doesn't start to play better.
This is a message board, not the Patriots PR site. Why would you expect people not to discuss what's going on? The only time that "Nothing else matters but wins" is true is when you're in the final game of the season, and it's winner take all. For every other game, it's not just winning that matters, because problems found and not remedied can be exploited by future opponents. I've been defending this defense of late, at least with regards to the "prevent" brouhaha, but let's not act as if those with concerns are completely without reason.
1.) It's statistically the worst defense against the pass in New England Patriots history, or at least it was heading into this past game. I don't think it's wrong of people to want better than that, regardless of the team's record.
2.) You've found the big problem, IMO. This team is winning a lot more on scheme than talent right now, at least when it comes to the defensive side of the ball. That's why a team like Cleveland was able to beat the hell out of them just by negating the scheme advantage. That's also why things need to improve. The coaching generally gets better in the playoffs, and weaknesses have had all season long to be exposed.
It's not all about total yards, it's about total team, so you make sense there, although the Chargers would probably have beaten the Patriots if Chargers players actually knew the rules of the game at the NFL level. But, if you think that means you should just ignore the problems of the defense because the offense is playing so well, perhaps a hearkening back to the Super Bowl in 2007 would serve as a nice refresher for you.