IMO, chemistry isn't about how the players interact off the court because it doesn't take them to be friends to understand each of their respected games, but more of a general respect for each other. It's understanding the strengths and weaknesses of your teammates, knowing their tendencies, what are they most likely going to do during here and there, what are they going to be doing here and there, being able to play without vocals as you can speak through each others eyes. i.e. Camby's ally oop passes to LMA is an example of that. I don't think it takes LMA or Camby to buy each other breakfast in bed to make that happen.
I think the chemistry on the court leads to more friendlier interaction off the court.