I'd like to see him hold onto his 7th YE#1, but he has to listen to his body, and also see where he is now mentally.
One issue is that tennis has a very short off-season, and I think he'll want to be at his best for the AO.
But if we concede that OE Goathood comes down (for now) to The Big 3, I don't see either Roger or Rafa catching him in YE#1s, or weeks. There is a chance Rafa can capture a 6th, but will he be healthy, motivated and in good enough form to do so for a full year?
As discussed on other threads, when you look at the Race to Turin numbers, his lead over Med is not insurmountable -- 1,990 points with at least two M1000s to come, and of course, up to 1,500 points at stake at the ATP Finals. How big of a push will Med make, and can he keep his excellent HC form? Z and Tsit are mathematically alive, but one of them would really have to run the table.