To be fair to Schweinsteiger, he's been absolutely mullered since breaking through, for both Bayern and Germany, in '04.
Averaged 52 games a season since '04 and since '08 he's averaged 56 games a season. Now for a box to box to play that amount over such a long period of time would kill anyones legs.
Especially considering how dependent Bayern have been on him. That's like 5 seasons - near 300 games.
He, like Evra, needs to be conditioned carefully. Think this is actually on cos' Honigstein said United were offered him when they wanted Kroos, Hunter says Guardiola doesn't like Schweinsteiger's style of play, Bayern have replacements and are over-stocked, he's 30 in Aug. and for £15-20M it would be a tempting offer.
Wonder how much he'd go for, possibly £20M?
United could get Bastian, and then a younger future star: O.Torres/Clasie (somebody like that) and just flourish.