Face it folks, nothing works 100%. People get distracted and into the scenery, their music or conversation with someone they are walking/running with. Sometimes they are just digging deep like we do sometimes when we suddenly come up on a stop light or stop sign. Yelling and making noise will often just startle someone enough to make them jump right in your path. I know how I feel when a car comes up quietly behind me and honks.

The best thing I've found is to call out as early as possible so you have time at a second chance before you come up on them. Then give them as wide a path as possible. I always say thanks when they move. The last thing i want to see is a wlker going to the city council to complain about being "buzzed" by cyclists.

Compare this thread to one of the many about how the motorist don't respect our right to be on the road and you'll realize their are two sides (sometimes more) to every complaint.

Just my two cents. Now play nice.