I'm aware. But that doesn't mean you have depth at a position. Just because the Spurs have played Blair and Diaw at C from time to time, that doesn't mean they can play C.
Green is more of a wing than a natural SG, but I've never liked Ginobili at SF. Not to say he can't ever play the position, but he's a guard. I've seen timvp's stats, but the reality is the Spurs don't put him on James, Durant, Anthony, Pierce, Gay, etc. When he plays SF, it's generally against guys who aren't threatening offensively players and/or overwhelmingly big. Now he'll have to play 15-20 mpg irrespective of the match-up and he'll have to guard some of those guys. Toughness only goes so far.