Thanks for linking that. Perhaps I should have been more clear.
While some of the things done to Guantanamo detainees qualify as "torture" under the UN definition (e.g. waterboarding), I can imagine a smart and determined psychiatrist working around that definition of torture and yet leaving a person in a psychological state which makes clear the immense immorality of their work.
In other words, there exists a set of "enhanced interrogations" that are not technically torture (in the way that waterboarding is), but that are still morally abhorrent and would likely be prohibited if revealed.