[infectoid]

Well... It's easier to nudge people into doing something than asking or demanding. They then think it was their own decision.

e.g. "It's important that you act naturally at all times and only within the limits of what you are comfortable with. For the purposes of the experiment you should also carefully consider your role as guard and what those duties might entail. Sometimes you may need to speak confidently in your role for people to listen to you."

Or some such thing. I am by no means a master of nudging but you get the point. You can ask a thing with out actually asking.

I think many people do this without even realising.