The voice thing works way better than people want to admit. I call out "on your left" from like 50 feet back, then again closer if they still haven't moved, and I keep the bell for when someone's actually looking my way. One thing that helps a ton is calling it early and then going quiet so they don't get startled twice. Also slow down before you pass, not during, because if you wait till you're on them it's already too late.

Ever think the fussy guy's chicken was just better because he was paying close attention the whole time, not because of the gram scale? Like the real variable is care and focus, and numbers are just one way to force yourself to slow down and notice stuff. Carlos in my old kitchen nailed it with a pinch and a feel, but he also never once walked away from the bird.