to me i believe it to be the ultimate stalemate.
on one hand yea superman could end it at anytime. if he really wanted to, he could destroy batman in an instant. but he won't.
but on the other hand batman could also end it at anytime. he HAS kryptonite. but like superman... he won't.
the mutual respect they have for one another is too great. they are like brothers.
if shyt were to ever go down and the 2 of them actually had to fight, it would basically just boil down to who acts first. because whoever acts first would be the winner.
Superman should see Kryptonite miles away using his X-ray vision. He can also attack Batman with his heat vision from a safe distance. Plus he's as fast as Flash so there should be no way a normal human would be able to see Superman move at his maximum speed. Superman can just toss buses, large boulders, houses from miles away at super speed and Batman should never be able to duck any of those. shyt, Superman should be able to take a baseball and throw a fast ball at Batman from 100 miles away and kill Batman with it. If you take Superman's powers and apply real world logic and strategy on using them, he would be able to kill every single person at superspeed without anyone knowing what happened, even from great distance.
Writers have dumb Superman's powers down whenever he gets in confrontation with a human (Batman or Lex). It's stupid and a reason why I never read Superman comics (aside from Red Son) and also another reason why I appreciated The Authority because those dudes used their powers like how people would really use them in real life.