I beleive the playing style itself is the problem. I believe he's a manager who knows his job very well, he makes players play his difficult style extremely quickly. But that style is about perfection, players have to do everything with full control and composure. They're not allow to take risks with their technique, everything they do they really have to master, get every touch right, 10 out of 10. But players can do a lot more when they're allowed to try things at the max of their ability and risk loss of posession. With Messi and Iniesta he got away with it, allthough he probably should have won more with that group of players. With Bayern he didn't, and in the PL with it's high pace it's even more difficult.