not too shabby general. looks like he worked on everything:
his sky jump slam, his net game, his between the legs shots, you name it.
Even his falling down shot... that's a rarity to see him fall. I hope the courts are ok.
But more interesting always is his choice of hitting partner. Marin Cilic is another young giant, 23 and almost 2 meters tall (6 ft 6).
I don't think Federer wants to be surprised by Isner again after the Swiss Federation messed up and put their Davis Cup match on that high bouncing clay. Or the likes of Raonic or Del Potro. He probably figures he'll have to face one of them at some point.