@c_9@mstdn.ca A lot depends on the implementation. I used to regularly pass through a traffic signal in Alexandria, Va., USA that defaulted to green but would change to red if any car approaching from either direction was exceeding the speed limit by 1 m.p.h. No matter how good your own behavior was, it invariably turned red any time more than one or two cars approached. It had no discernable effect on speeds elsewhere on the same road and surely generated ill will towards the local traffic laws.