An interesting video: Finger Versus Table Saw, with Bourbon Moth’s characteristic humor.
It seems he didn’t get as many triggers as you might expect. We at Asmbly know that laser char can sometimes trigger the stop. I know from my own experience that the aluminum miter slide will set it off (no surprise), but I’ve sliced through a brass screw without triggering it.
I’m pretty sure the trigger works via capacitance changes, which explains why borderline cases are so unpredictable. The quantity of material and the exact geometry will matter then.
I do wish he had tested treated wood. Though of course we discourage people from using treated wood here.