Ok then, what about a rally car with the co driver's life in the hands of the driver? Should the driver not accept someone in the passenger seat? Or indeed any passenger, riding pillion on a motor bike? Motor Cycling on public roads is far more dangerous than bondage. In the UK several hundred motor cyclists die every year. I just don't see ordinary bondage as very dangerous as long as you don't do anything deliberately stupid e.g. Leaving someone gagged and/or hooded.