Apparently Roche is highly reluctant to spend time with any player other than Federer. I remember that he was persuaded into coaching Sania Mirza (although it isn't related, her career went downhill from then on) after a lot of effort.
If I were you, I wouldn't believe this unless it was from a really trustworthy source. Can't imagine Roche coaching even Korolev, JMDP or Gulbis...
The results can only be brilliant if this is true.
Roche is allowed to work with anyone he wants, mind it. He doesn't have any sort of contract with Federer and is paid by the week or by the month.
