Uncle Abraxas with an over discussed thread again. Sounds boring.
The threads you create are a whole lot better right?
Eitehr way, I think Rafa can take one at Australia. US Open might be a bit of a stretch while Wimbledon will always be a good one for him in general, but really, this type of question will be best answered after the US Open so we can see if there is a pattern happening or if this is just one of those low periods like he has had several times in the past.
I think for me the more interesting question is if Nadal will ever defend a non-clay title. I mean just from the top of my head, Indian Wells, Wimbledon and Canada are the only 3 non-clay events he has won more than once.