This squares with my own experience riding in Miami. I can't remember the last time any cyclist overtaking me on the M-Path or the South Dade Trail called out or used a bell to let me know he was about to pass.
Al Melvin on the South Dade Trail
My friends, we have a problem here. As much as we want to see bicycling increase, I can't imagine it will grow very far until we look out for each other better than we have been doing. How much trouble is it to sound off -- "Passing on your left" -- when you overtake a walker or another cyclist? You know you can do it. And Al and I are counting on you.
-- -- --Al has written more about his trip at Florida Biking Adventures.