I did a 3 day E&E in Germany in the early 70's as an officer cadet. Was captured and interrogated (KOSB's I think) - sack over the head, water poured over me, stripped to underwear and paraded through the local town (not sure where...). Can't remember how long I 'resisted', but I didn't regard it as particularly harsh - not as bad as the 'tear gas' experience.