When Pep released Gundogan from a more defensive role at Chelsea last season it changed everything. He's not a DM never has been never will be. But he's done the jobs he's been asked to do. Probably missed more football this season because he's passed his peak. That's not a criticism just a fact. Knowing when to move good players on is the art of keeping continuity of success. The last two managers who were good at that were Paisley and Ferguson. And Ferguson started to slide when he failed to do it. Pep is still at his managerial peak and he knows he needs to freshen things up to keep moving forward.