They might have 12 players injured but first XI players? Really?? You said first team players admittedly but quite a few of them are subs / squad players and it's not as if they really miss all of them. Some kid goes on and on about the same thing in another forum but it just doesn't wash with me. From the list he gave a week or so ago, half the players were shit and hardly get a game anyway. Out of the list (I haven't seen the one you are on about), how many players would you really miss out of the 12? There are some good ones missing that I can think of off the top of my head but not buying this number 12 as some are there to just make up the numbers.
The last two games we've been without: Rooney, Vidic, Nani, Cleverley, Anderson, both Goalkeepers and Ashley Young. If I were to put together a 'first' XI, at least 5 of them would be in it.
The only 'insignificant' injuries we've had this year have been to Owen (yeah he's still around) and the twins (normally one is fit, and they're reasonably interchangeable).
The only player in our entire 25 man squad that has been fit for every premier league match this season is Park.
Finally, in United's 34 matches (before Stoke) they've fielded 22 different combinations in defence. Hence the shakiness.