Demand traffic lights using a loop sensor that can pick up a car through magnetism are nothing new. They can be a problem for cyclists because many bikes don't have enough metal.
There used to be a traffic light in Ithaca where if you were heading out of town via the South hill you could bypass South Aurora St and instead go up a residential street up a steep hill with very little traffic, hang a left and trigger the light and almost always get the light to turn red in front of the person who was in front of you on the main road.
There used to be a traffic light in Ithaca where if you were heading out of town via the South hill you could bypass South Aurora St and instead go up a residential street up a steep hill with very little traffic, hang a left and trigger the light and almost always get the light to turn red in front of the person who was in front of you on the main road.
They retimed it so this didn't work anymore.