Highly dependent on engine, exhaust, and O2 placement, but is there a "starting point" difference to notice changes? Stock delay is in the 2-300ms range, so is +/- 50ms typically enough to "feel" if the delay change is the right approach?

Doing this by SOTP since I don't have wideband (I know, I know), but the off-idle problem is enough that I will know immediately if it is helping. No matter what the BLM is at idle (whether rich or 128) stabbing the throttle results in an immediate jump to a lean condition, which I can't get rid of with just AE.

I've never dealt with this one before. I know some settings a minute change makes a huge difference, and others it takes massive changes to see/feel a difference. I'm thinking 50ms is a fairly large change

I don't have a Camaro manifold to get a baseline distance to where it is now, but the (heated) O2 is in the collector on long tubes, so I'm guessing it's three feet beyond stock. Using an arbitrary 5" from last exhaust port to 36" to O2 now, 50ms added to 300ms would be nearly perfect as a percentage. I assume however that the theoretical increase in exhaust velocity from headers will skew the results.