CRM for Private flying?
Taking up friends or family as passengers in a light aircraft, we have responsibility for their welfare. Of course they trust us, and we don't want to frighten them.
And yet. Just as in DownWest's reference to the youngster who "didn't want to ask a senior officer if he knew what he was doing", I believe it could be useful to include in the preflight briefing for your pax a way of asking for their feedback if anything about the flight is worrying to them.
Like flying into bad weather, flying too low, whatever. "Dad, do you mind if we stop for fuel and a coffee, I think you are getting tired."
How would you react if your teenager was bold enough to suggest that you were less than perfect?