Schniederlein and Di Maria footballing wise were bad transfers, but on the flip side we sold them for almost as much as we paid for them so they cannot be classed the same as some of the other names listed
I agree to an extent, but also can offer a counter-perspective and viewpoint. Context can sometimes be everything. Allow me to wax poetic....
When it comes to Schneiderlein, in retrospect - he can almost represent and be like a "post-modern avatar", that canary in the coalmine, that represents our "like of bite in the midfield." That gaping hole since Roy Keane left. Either a "midfield enforcer" or someone who can "tick things over" like Rodri or Carrick. Every season we hear the need for it, every year it comes up short. It's part of the intrinsic story of Manchester United over the past decade -which is what we're talking. He was supposed to be "the one." Like Ugarte is now. Or countless other defensive midfield signings people have posted thousands for on the Caf. The lack of that person on the pitch, is a huge disappointment, regardless of whether we made money on Schneiderlien himself. He represents the lack of a midfield solidity. That was a huge disappointment on the pitch.
As for Di Maria, he was the "coup", or the "silver bullet", if you will. Far from being "washed up", many thought he was a jewel in Real Madrid's crown. He didn't want to come here, it was well known he was being forced out of Madrid. And we did it ... anyway. Hopes dashed. Precious time spent to get him out. A year wasted on spending time on him, which could've been focused on other things, like finding a decent defensive midfielder. No team, much less Manchester United, likes to know you're "second best", not worth being here for, or worse, just a stepping stone to the next job. He mugged us, and tarnished our reputation. He basically said, "You are beneath me, and I'm just here until I get my next gig." He may have actually been worse than than all the others combined. He wasn't so much a disappointment on the pitch, or financially .. he was worse. He was a dagger into the heart of Manchester United fans -> He didn't want to be here and he couldn't care less. I hate his rat face.
I'd take a dogged-ass Rooney, on his very last legs and huge wages, in his very last match for United, who was at least trying over Di Maria on his best day.