Nadal will return and win RG, and Wimbledon is possible with a good draw and some luck, but he is done at winning anything above 500 on hard. The sensible thing to do would be to only to play enough HC tournaments to maintain a top 4 ranking and consequently save his knees and prolong his career.
Too many people are saying this. Sorry, I just don't see it that way. He narrowly lost AO 2012 against Djokovic - the current king of AO - and previous to that he made the USO final.
If he comes back good enough to win RG, why can't he make the final days of the HC majors and give himself the chance of winning them, like he did earlier this year?