I've had the hook on my strap hit a running prop. I was lucky in that it only bounced back up and smacked my ear (my pride was more hurt than anything), but just that little bit got my attention. I make it my habit now to put my neck strap around my back so it's hanging down my back. Since it's part of my routine now I feel strange when I forget to do it, and stop to figure out what is wrong. If you develop good safety habits they will usually kick in when our brains stop thinking!!!!
Ken