Originally posted by Joe Gardner
I only use "on your left" when passing other cyclists, rare in itself! For passing joggers, or kids, i usualy yell "coming through!" 3 - 5 secconds before passing, this gives them enought time to get out of the way, right or left, and let me pass. When they do let me pass without issues, i usualy reward them with a thank you.
After a day of riding on an organized tour last year, I was walking down the sidewalk on the university campus where we were staying. The walk was crowded with pedestrians going both directions. A voice behind me yelled "On your left!" When I'm riding, I know how to react when I hear those words. When I'm walking--on a sidewalk no less--it's the last thing I expect. I turned to see what the yelling was, stepped into the path of the oncoming bike, and we both went down.
When I pass pedestrians, I do it slowly. I don't yell anything. I start talking and braking well in advance. I say things like "Hi. I'm going to pass over here on your left side. Thanks. Nice day, isn't it?"