I think if we spend anywhere close to 30 million for a striker and then 15-25 more for a Midfielder and CB there is no way We will bring Cesc back. United will bide their time and watch us spend 50-60 million , knowing our board/Kroenke wont spend anymore. After all we allowed our captain already to go to our rivals , if Cesc goes they wont be bothered.
The right thing to do of course is send Gazidis to Madrid on holiday , get the press all over it and make United look silly, and if it comes to Barca then selling take Cesc back.