We really need to move away from this thinking as ironically i think it is that what is small time - if Alderwiereld wants United and they want him then the deal should have been struck during last season to conclude when the window opens - we then get on with improving our team with the added 50-60m or whatever is.
fudge United, if they don't get him they'll blow big money on some other highly rated player anyway - biting our nose off to spite our face by keeping hold of a player we aren't going to use isn't making a stand or a point, it's just holding us back and making us look petty.
It absolutely is a statement of intent.
It was, and is, real enough that Mourinho moaned about it last year when comparing United with (I think) Bayern - 'do you think I can take the two best players from Tottenham? I can't, not anymore.'
It is a precedent that has held for almost a decade now - come what may, we do not sell to our rivals. It resonates with players, managers and fans alike.
It matters.
Although, of course, we could do it your way as well. We could become a low-grade version of Arsenal from 2006 to 2014, hawking our players to any club bigger than us that can afford to pay.
And didn't that work out *well* for them? They lost Adebayor, Sagna, Clichy, Nasri, Van Persie...the Manchester clubs pillaged them and left them with nothing in return.
But I'm sure they were happy they weren't being perceived as petty. And how big and important they must have felt, watching their best players leave to United and City every year while they scraped 4th and stayed trophyless throughout.
Would you like that to happen here? Because it will, once the floodgates are opened. And remember, our base is far lower than Arsenal to begin with - they had won titles and trophies galore before moving into their new digs, while we gave won absolutely nothing for a decade, and precious little of vslue after 1991.
I repeat, selling Toby to United without getting Martial in return is being offered by a big club that will congratulate us for not being 'petty while making off with our best players.
It is cutting off your nose for no appreciable benefit whatsoever.