My opinion - Fed would win average 2 Slams a year, Nadal and Novak 1 each. But that's all could've, would've, should've. Maybe Novak would break out 1st and destroy Fed few times and develop his game in a different way that wouldn't suit Federer. Maybe that would be his main goal - like he changed his style in 2011 in order to win, maybe he would change his style to be more aggressive or whatever in order to stop Fed. Maybe Fed would (wrongly) change his gameplan after getting owned few times and we would never see his true potential. It all looks easy now 'player's A peak > players B peak' he would win everything. There's bunch of stuff that could influence each of them and they would become different players (like a different coach for example). It is what it is, we can never know what would really happen.
Correct. The variables would change. If Novak could go back in time like Marty McFly, everything we know today would be different, including the number of GOAT gloryhunters on MTF. Can't imagine what Nadal and the Falcon would have done to Fed's confidence and mental game. It's easy to play godlike tennis when you really outclass your opponents (refer to some of the pigeon and turkey head to heads), its always the same NID types of matches over and over again. Throw a wrench in that confidence and it's a game changer.