Courtesy crossings are successful when integrated with traffic calming. They work very well together.
Pedestrian psychology has to be taken into account. People work best when the options are natural and are clear cut. Much like like when pedestrians are more comfortable around one land of traffic.
In order for drivers to make the choices you want them to make, their phychology must be taken into account. If you want them to be courteous to pedestrians, what must the public realm do to influence that?