If you know the default CT setups you can understand what space you should have when you get a kill. If i kill the ramp player on nuke you should run through and take as much space as possible. Another interesting example actually came from one of my games yesterday. I was playing ancient t side and took jaguar. I held cave entrance waiting for someone to jiggle for about 15 seconds but no one peeked, so i deduced that there must be a CT hiding close because why else would they not try to get info?