The two roles are not comparable in my opinion. In most cases an instructor of humans has no capability to control the car. I've heard of some cases where they

The two roles are not comparable in my opinion. In most cases an instructor of humans has no capability to control the car. I've heard of some cases where they have brakes installed on the passenger side, but I'm not sure how common that is. I've never heard of a teaching car with full duplicate controls, though it's certainly possible they exist. I think even a bad new human driver is still better than an Uber automated system at the moment.