I dont think Cesc is all that bothered frankly. Before he moved he must have had a good idea of how Barca would play him regarding position and game time. Hes been played quite a bit frankly but yeh considering he started when he could at Arsenal its only going to a minor disappointment. Im pretty sure he will win a trophy next year, the year after and probably the year after that...but maybe (very wishfully thinking) Barca have burnt themselves out and will be falling from grace.
I think what Barca proved, if anything, is that it is hard for a dominant team to keep dominating. According to Pep that was one of the reasons he kept trying to bring in new players so that there was enough new blood to keep the motivation going. I think for Barca simply can't charge themselves enough mentally any more tp dominate and as we have seen at Aresenal the tikkie takkie football can fall apart real quickly when it does not fire on all cylinders and when it does not have multiple threats up front.
Pep always tried to have a top striker and kept that position "fresh" recently he had Eto followed by Ibrahimovich and David Villa. Today's Barca made the mistake to rely too heavily of Messie and with out a real out-and-out striker up front (Villa was injured most of the time) Barca's fortune came and went with the form of Messi.
It will be interesting to see how long it will take them to rebuild.