I must agree Federer is currently playing the best tennis since he started to decline.
Can you picture Roger 2008-2010 beating Nadal at Indian Wells? Because I can't.
I believe Fed is enjoying a sort of short-term Renaissance of 2004-2007 form.
The only top 4 players that seem to be declining are Nadal and Murray a little bit as well. Nadal and Murray were better in 2008-2009 than now.. Meanwhile Federer and Djokovic are better now than a couple of years ago.
I wouldn't be surprised if Nole and Roger share the slams this year.