I was just going to say has anyone tried increasing the ratio to 2 and seeing if it increases accuracy?Keep in mind those images happen at a one second interval. That can be self defeating if the motion is of short duration. I'm using 1 or 2 depending on the camera location and what I want detected. This is another case of how important it can be to have the iframe rate set the same as the frame rate since that insures a full frame every second and motion detection starts on an iframe.
The penalty is going to be much larger recordings and possibly increased cpu as DS now has to analyse 2 frames (need to set it to 2 in DS settings as well).