The only one that caused me any anxiety was a friend I took on a return trip from LPL to Shobdon. Gave him all the usual briefings before both take offs and even gave him a reminder on finals about not touching anything. Just as I was in the flare on the homecoming to LPL, (there was quite a strong crosswind so I was crabbing in) he decided to stretch his legs and pushed really hard on exactly the wrong rudder pedal!