He looks to be strong and in shape so I'm not really worried about his physical recovery. If it really was "can only jog for 5 mins bad" then he would be nowhere near the shape seen in recent photos.
As they are scheduled to have a child soon maybe he doesn't think it's worthwhile to start up on the tour until that is over and all goes well. I mean the ATP tour is a lot of travel and him and Jenni might have decided that it's the best to just take it easy, avoid the media attention that his comeback would cause.
Would love if he gave USO a shot but I'm thinking he'll delay it possibly all the way to Stockholm Open or even next season. Then when he comes back I wouldn't be surprised if he's superstrong physically and more prepared than ever. I think he'll shock everyone because he's a known training fanatic and being able to have a "off-season" this long could turn out to be really good for the next 1-2 seasons.
look pretty fit in those recent fishing shots