I think if you go to the biomedical community, they know quite a lot about which kinds of programs have been successful and what kinds of things have not worked out very well. I think scientists are actually sometimes extremely good at measuring this.
If I may, I will say one thing in response to one of your other points. For many years I have taught courses in contemporary moral problems. I have had students in those courses who have held views far more conservative than mine. I've also had students who have sometimes held views far more liberal than mine. None of those students has ever felt intimidated or unable to speak up in class. I mean—