How will you stop them travelling on your plane LSM? And how can you be certain that the passengers in the emergency exit rows have been given their "one to one briefing" and have accepted their responsibility? The truth is passenger evacuation procedures are one of the holes in the Swiss cheese and sooner or later it will line up with some other ones and a lot of people will be dead. On the one hand in this thread there are posters, mainly passengers but a few CC saying in reality the evacuation procedures are flawed, and on the other there a few saying that its nothing to do with manufacturers or airlines, its the passengers who are a problem. Maybe you should find another set of passengers.