Keep in mind, when Novak turned into the world beater he was in 2011, most acknowledged that it was largely small adjustments making a huge difference. Tennis is a game of inches, and him defending a touch better, counterpunching even more lethally on a consistent basis, playing with controlled aggression without losing patience, getting his forehand to miss less, and getting back his serve meant going half a season undefeated. In each of those areas, the actual difference in what he's doing was not that big compared to before. But when you combine them all together, they make a huge difference. Now, in the subsequent years, a slight drop off in each (but not big enough to where he's back to his 2009 self) means he's still an amazing player, but all of a sudden, he's beatable. That's tennis.
PS: It's not a Cali thread without a hyperbolic, over the top title for shock value.