Simple question in some regard.
Of Nadal's 14 Slam titles, 9 are from the French Open.
Djokovic has 7 titles with 4 of them from the Australian Open.
Djokovic however has 14 Finals to Nadal's 20. Including 5 at the U.S. Open and four consecutive (to Nadal's 3 overall). Djokovic has as many Wimbledon titles as Nadal with more opportunity to gain there yet. Meanwhile at the French Open, Djokovic continues to be pegged as the strongest competitor to unseat Nadal.
I think Djokovic, as always, has a fair shot in winning the U.S. Open. If he does that he's obviously the favourite in Australia. Winning those two titles before French Open 2015 would put him at 9 and behind Nadal by 5. Of course winning the 2015 French in that order would give him all four Slams at one time and a place with Rod Laver. It would give him 10 titles and what both Federer and Nadal never achieved.
The opportunity is there for him.
Getting to 15 titles is unlikely though.
Well, you are another one?
I mean, I have this feeling that Novak can hold all 4 GSs after 2015 RG.
For some reason I have no feel for the rest of his career, weird or what?
If he goes into Novak 2011 mode, than he could have great few years with Murray maybe never coming back to top form, Nadal declining, Roger old and most new players not that great (Dimi apart).
I put him on 11-12 on the basis that his 2011 mode did not last and he is too old to wait for another 2011 mode to occur in his 30's.
So with winning next 3-4 GS in his 2.0 mode and one a year in 2016, 2017, he might end up with 12-13.
I would be amazed if he caught Nadal, although I think Nadal is done with GS, unless Novak gets injured.