I don't know whats going wrong, but united's problem has been that rooney rvp and mata arent passing to each other, less than 10 passes between any pairing of those this season, which when theyre supposed to be the source of almost all your offense, is kind of a problem. This isn't something thats an inherent problem the 3-5-2 usually has either, so something odd is going on (i still blame it on the lack of midfield presence, they need better. Di maria doesn't fit well in the double pivot and they have no one else really).