I agree that larger sample size will eventually average out some of the anomalies, but they are doing something right, as Busquets who didn't score or assist, was second only to Messi, who directly contributed to all three goals, which gave the win, and which was confirmed by the collective subjectivity. As for Pedro Leon, yeah I can't say why because I don't really follow him that much, but from Opta ratings you can basically see why he is rated. And I didn't hear any arguments for why Xavi would have performed better this season than him.