It doesn't matter with the excuses.
What matters is what's in the record books.
We will see how Murray and Djokovic do this year, Fed is still #2 by a good margin.
Nadal is back and hoping to see him perform well.
For the first time in his career he has rested his body and hopefully his competitive fire will shine.
It's been reported that his knees are fine but still bothering him some, if it's only that then he knows how to deal with it.