you mean cyclists actually stop for lights?

apparently some do
so you strap this monstrosity to your bike

and it triggers the sensor in the pavement
you know the thing you try to get your tire over at the light...
so not only would you still have to stop, but you have to try to get 

that ugly ass thing over the right spot at an intersection...

probably with no traffic in sight...

let me go on the record here...

"i have never stopped for a red light"

never

not even with a cop at the intersection

which happens quite a bit

more here at gizmodo