I guess it is self explanatory. It seems to me that it will pass up better city spots to settle directly next to you. Is is some kind of eventual war strategy or something? Because I sure don't get it. I played a game last night where Morocco did this. I was getting ready to annihilate him when the Hawaiian snitch made his inevitable appearance and immediately became friends with him. I can't count how many times I've had a city state next to valuable natural wonders or some civ like Morocco needed to be wiped out, when this jerk shows up as if he is the world's busybody - "I'm telling, I'm telling!".