Passing accuracy has nothing to do with anything, it was just down to the style they used to play, the lack of risk taking, and their position on the pitch (Modric covers a wider range than Xavi, and plays a bit further), but we're comparing their ability here, and when Modric is trying to not lose to ball and find solutions, esp. in tight situations, no one else comes close to him, you can put three opp. players on him and he can keep the ball for as long as he wants with superb control, little feints, change of speed etc., and easily finds his teammates, Xavi has nothing on him in this regard, neither does Iniesta, as great as he is on the ball.