I found an article similiar to the link below several months ago. After reading it I determined that I had been doing this kind of thing my whole adult life. I don't know why. I've jsut always been a little hyper-aware. Ok... maybe I was just untrusting and leary of some folks. However you want to say it, it's just good sense. I had my 9 year old daughter with me the other day as I went to Wal-Mart. As we walked through the parking lot I thought it might be a good place to bring up the topic and use the parking lot as an example. Not only did she get it but several days later she told me a story of actually using it at school to avoid some kids causing problems. It was the "AH-HAH!" moment every parent dreams of. So...I surely didn't come up with this concept. I'm not sure of its origins. I do know that it works. I'll post the link I found and will repost the original story I read when I can find it. Oh yeah...y'all have a good 'un.