pass completion rate means nothing, most of xavi passes are to iniesta, pedro or messi, but they are not the dificult passes. the kind of passes that makes you think that hes
good
and assist are attacking passes
if you take mascheranos completion passes, you'll see he has around 90 percent, only becaise he always passes the ball to a player that's less than 6 feet away
as i said, what proves you are a good passes are the assists, because those are the diffucult passes. the one that every defender is waiting and care to stop