Well contrary to what people like to think we don't have a rivalry with barca, yes they are cunts but we don't even have to think about them unless we're playing them, the history just isn't there to create a rivalry and a few games in europe won't change that. AC milan and liverpool don't consider themselves rivals even though they've played each other in two finals. The history just isn't there for me for a rivalry with them.
Unlike with man utd where you have years and years of us competing against each other, giggs goal in the semi final, keown and van nistelrooy, when we lost our unbeaten run, stapleton going to them, winning the league at old trafford. There's years and years of history there, we're not rivals with barca because they buy players off us either, if we were then man utd and madrid would consider themselves rivals over beckham and ronaldo.
To sum up I hate man utd far more than I hate barcelona, barca are just another cuntish club full of divers to me that I don't even think about unless we're playing them so cesc going there is a small issue for me inspite of the way they all went about it. Man utd for me represent a much bigger hate figure and van persie going there as our captain knowing all of our history, playing in the fa cup final against them and being at the club when we lost our unbeaten run was the act of ultimate betrayal that I can never forgive.