Originally Posted by SF Biker
There is a reason that on EVERY organized century one of the rules is "always call out, on your left".
I have yet to see this rule on any of the century rides I've done. And the most warning I've seen on bike paths is that you must make an "audible signal" prior to passing. The main path down here (Los Gatos Creek trail) requires that you "reduce speed by half" when passing, with a maximum of 7.5 MPH (trail speed limit is 15, and they do enforce it). I used to be an "on your left" guy on there, but the thing is, people are generally clueless. Most think it means "move left"; exactly the opposite of what you want them to do. Many don't do anything, even crowds of people. I just gave up on riding the trail for anything more than a VERY casual ride with my family.
My thought is: I don't honk the horn of my car when I'm about to pass someone; it's my responsibility to pass safely. If you're passing someone so closely that you feel compelled to say something to warn them of your presence, you're probably too close.