The point is though, look at the midfield they have... and they lost the league on goal difference. Between ronaldo developing and giggs becoming slow is the only time they havnt really been up their challenging. Uniteds team last year should have been no where near city`s but they was because they have pace on the wings. Valencia, young nani are all a massive threat. They can stretch teams and get in behind so quick.
You have a point, however, on the flip side they lost the league by not having the defensive cover in midfield when their attacks broke down thus exposing their frail centre and putting massive pressure on their weaker back four.
The bottom line is United just have this knack of winning when they are playing shit, the amount of times they have pulled a result out of no where is beyond belief, thing is Liverpool used to do exactly the same years ago.
Mentality of visiting sides to the toilet is a big factor too, half the PL turn up there with the mentality that they are starting the game 2-0 down before a ball is even kicked, it has been different in recent years in that a half decent PL side will go there and give it a go, again see the Bitters game last season. Their invincibility is starting to wane, a bit like opposing teams visiting Anfield now, they are not so afraid anymore, I think we will see more teams go to Old Trafford and actually play to get something because they are not what they used to be.
I dare bet that they are not even 6 points within Manchester City next season and maybe even Chelsea given the level of investment that Chelsea have already made and what City are likely to make.