"the whole concept of information gathering through gossip collecting, innuendo, accusation, leading to torture - these are all medieval methods fuelled by bias and necessity.

but they are not accurate."

But under certain circumstances in the light of absolutely nothing else, while not being necessarily accurate - it is a damn sight better than nothing.

Oh and your first part about "intelligence" being "such a useless word, describing information gained through any ways but through verifiable evidence." What about independent corroboration Freda? In interrogating a large number of people who are kept apart the likelyhood of them holding to a lie while under pressure is a great deal less likely than than coming out with something that is true. Because when someone is disorientated, tired and apprehensive to tell a lie is something you have to think about and have the mental discipline to tell that same lie the same way time after time. The truth on the other hand just comes out.

Situations vary as do time scales for getting results an ordinary soldier captured will probably have to remain quiet for about six hours before any information he had becomes useless - dark, quiet, no means of marking the passage of time, let his own fear and apprehension get the better of him. Wheel him out after a couple of hours into a prepared environment make him think and believe that it is later than it is, sit him down give him something to drink and talk quietly to him - you will get information that you can use.

Another instance - an attack swimmer pulled out of a naval anchorage - now the information he has got you need to get rather faster, otherwise a ship and it's crew could be lost. This individual is going to be handled that much rougher, if placed with the choice of bruising someones feelings or suffering the loss of a ship and her ships company - them feelings is going to get rather severely bruised.