They removed all the "Yield / Unprotected Left Turn" lights in my town, just for this reason. People simply don't understand. It's a bummer to sit and wait, but it does save lives.
I guess I don't even follow what this means, does every single stop light where someone could possibly turn left now have the green arrow in your town? That seems ridiculous to me, coming from a city where thousands or tens of thousands of stoplights would need to be retrofitted just because people don't know how to turn left on a two way street.