I find a lot to agree with in this.
I don't think trying to buy a player that you want is ever a bad thing. Even if the player turns you down to go elsewhere. We tried to buy Ronaldinho once. He ended up choosing Barcelona. It wasn't a bad idea to try to go for Ronaldinho. Sometimes you go for a player and it doesn't work out. That's life.
I dunno how many people on this forum have ever tried to hire someone for a job. Sometimes you want someone and they choose not to accept the offer, for various reasons. Whether we like it or not, cos we're emotionally invested in Man Utd, for a lot of players football is a job. When people move job they tend to consider a range of factors, they talk it over with their families, the people close to them. Sometimes you find someone who you think: 'Wow, they'd be a fantastic fit.' It just doesn't come off for some reason.
For me the big failing if we don't sign De Jong is not trying to sign him, its in not having a suitable alternative identified. That, I think, is an issue of planning that Arnold and Murtough should be held responsible for.