I would hope that he performs terribly at Madrid and he ends up on Real Madrids bench with Casillas returning to peak form. After spending a few years on the bench he will join a second rate CL club and when he faces United I would hope our attackers completely humiliate him and put 5/6 goals past him.
He's a quality goal keeper so I doubt that will happen, but I really can't wish him well. I remember when he was getting destroyed by everyone due to his subpar performances and the club stood by him through it all when a lot of clubs would have just replaced him all together.
If he signs a new contract and we get a world record keeper fee for him then all the best, but if he runs down his contract and does some judas stuff then feck him.
I don't share as strong feelings as you, but I'm bloody close. I think De Gea owes us at least another season or two. Fecking off now when we're possibly building up to a title challenge and need him most doesn't sit well with me.