During the Federer Korolev match, the commentators (I think Drysdale) mentioned that the slice and topspin sit up. At the US Open, it's not a factor for Federer because of the court speed, but the Aussie is slower so it was a factor here. They were then saying that a big flat hitter had a very good chance at success (i.e. Korolev). I don't get it. Isn't slice supposed to skid and stay low. For a low bouncing surface, like the Aussie (compared to the Rebound ace), it seems wrong.