I think that Federer's main problem is tennis officialdom. As long as they continue in their plans to make the courts as slow as possible then he will struggle. They have largely succeeded - probably only a handful of tennis championships now are on Medium or faster surface.
I know that, have thought of that also. But watch close if you don't already. Sometimes, for example at the Olympics against Murray, sometimes he comes out and has no serve, racks up unforced errors, it's very frustrating and sad, he's either on or not, when he's not he plays like a tired player, I've said that for along time, you can tell right away, his serve will be mediocre, hit the net, hit long, shank. In other words, he plays great, but not the Fed of '06. Go watch a video of him back then, he was insane, never missed anything, just a robot machine.
I mean we have to be honest or no one will take us serious, I agree if the courts were faster he'd still be kicking butt, but they are not faster, and he's slowed. If he can get through a easy draw, and play for example like he did against anyone but the last two at the AO, he'll win more GS's, he's still got it big time, more natural talent than anyone, but not when tired.