I took a PPl friend up for an introductory flight. Flying out of Wintervogel. Low cloud and it had rained earlier. Spent a long time in the hangers talking about the various aircraft, their different performances and handling characteristics.
Pre-flight done, I warmed the aircraft up.
Climbed in and before start up I gave a thorough briefing of all instruments, controls, parachute activator and the procedure for takeoff, holding points etc . All fine and instructions understood.
Mags on, prop clear, start up. No problems, I revved up to get rolling and asked for some brake.
Incident:- the engine revved up without my input, first reaction was to get to the choke. I asked for mags off—no reaction , I then pulled his right leg up off the throttle. Problem solved

Post mortem. A PPl will have auto memory and “subconscious muscle reaction†to respond to a thought process. Similarly this reaction has been postulated as possible causes of accidents in multi license pilots.
He pushed both pedals simultaneously when asked to brake.
Lesson learned. Comments?
Fly safely.
Graham.