I have been in your shoes before. Get out in the woods, get up a tree. look over and there is a hang on stand about 40 yards away.....oops. No one is in it and I generally dont scan the trees looking for other stands. If I see one I will move on just to avoid any situations like you describe. Once I was in the tree and and settled in I wasnt moving. Luckly the guy never showed up and it was never an issue. If he had shown up I would have probably moved out of the area because I had a climber and his was a hang on. You just have to treat others as you would want to be treated. Im out in the woods to get away and relax and hopefully bring some meat home. I wouldnt want to ruin my day getting into an argument over being in someone elses spot. Its public land and everyone just has to get along and have a good time