If someone is keeping to the right I'll not do anything. If two people are side by side or someone is in the middle of the path I'll ring my bell. Works well nearly all of the time now (it's taken a few years for people in Minnesota to get use to bells, but they have and it works much better).

I stopped using OYL several years ago. Low success rate and too many people stepped to their left instead of to the right, even after decades of people shouting it.