Look, in the last 4 seasons they've tonked everyone in front of them. Their style of play may not be to everybody's tastes, but it's undoubtedly one of the reasons they are so succesful. It's the most proactive way of playing football and when they are 'on it' there's virtually nothing any team can do to stop them. They monopolise the ball to a degree not before seen in in the game, and when you have the forwards and creative players they do, coupled with the possession in dangerous areas they have, you're always going to create lots of goal scoring opportunities, a lot of which Messi and co. usually take.
The 2 semi-final defeats they've suffered in recent seasons have come against teams playing skilled, backs to the wall football, but more than that they've come about because Barcelona have missed a host of chances. Against Chelsea alone they hit the woodwork 4 times, missed 2 open goals and a penalty. It happens in football and Inter and Chelsea did well to go through, but there's no indictment of Barcelona's quality or style there. And, as I'm sure everone will see next season, they certainly havn't been 'found out'.