Murray definitely had the edge in schedule and rest, so I don't think Fed's just a specialist now, I think he just didn't have the elements in his favour last night. Go Djokovic!
Funny you say that because one of the major themes leading up to the semi in the British press was that Federer had the edge in schedule as all his games were in the cooler night air, versus Murray's matches all being scheduled during the hotter day.