I was disappointed to see Charlie Higson on Have I Got News For You help - probably unwittingly - to propagate the myth that waterboarding merely 'simulates' drowning because no water actually gets beyond the victim's mouth. This is the Wikipedia description :
"Waterboarding is a form of torture that consists of immobilizing the subject on his/her back with the head inclined downwards. Water is then poured over the face into breathing passages, thus triggering the mammalian diving reflex causing the captive to experience the sensations of drowning. In contrast to submerging the head face-forward in water, waterboarding precipitates an almost immediate gag reflex. It can cause extreme pain, dry drowning, damage to lungs, brain damage from oxygen deprivation, other physical injuries including broken bones due to struggling against restraints, lasting psychological damage and, if uninterrupted, death. Adverse physical consequences can manifest themselves months after the event, while psychological effects can last for years."