The Post article you cite isn't a news article but an opinion piece, written by Bush's former speechwriter - this is not an unbiased source (nor are Panetta and Hayden, who Thiessen cites). Even if it were, it does not claim that such techniques were used to gain intelligence, but compliance. I've never argued that a torture victim won't usually end up doing what the torturer wanted them to do, but this is hardly the ticking time-bomb style case that you viewed as possibly justified. This is systematic torture across the board in hopes that it will one day provide something useful, not a specific case where time was essential. (Edit: he also specifically cites information gained by torture as useful in killing bin Laden, but as the following article in the NYTimes documents, the Senate Select Committee found that the info was gained from a man named Ghul before he was tortured:
https://www.nytimes.com/interactive/2014/12/08/world/does-torture-work-the-cias-claims-and-what-the-committee-found.html - essentially, as this article shows, the CIA under Bush spent years lying about the usefulness of its torture programs).
Roberts claims in the Daily Beast article that the 19 double agents employed by Britain were tortured into doing so. I've not found a single other source to corroborate this claim (notably, he claims no evidence, just that one would be naive to think that they were talked into it). On the contrary, the stories I've found thus far regarding three of them - Juan Pujol Garcia, Roman Czerniawski and Dusko Popov (Google their names, you'll get Wikipedia articles on them) - are all stories of people who quite voluntarily became British spies against the Nazis.
Here is a book written by the Intelligence Science Board on interrogation techniques and their efficacy:
https://fas.org/irp/dni/educing.pdfAs it notes, part of what makes coming to an absolute conclusion here tricky is that we don't have a lot of good science on the subject, since we don't torture people in lab experiments anymore. Still, there remain ways to test techniques somewhat indirectly, such as the following example from the book above:
"Under conditions that simulate an intelligence interrogation, indirect strategies for eliciting information (i.e., acquiring information through interaction by means other than asking for it directly) may be more effective than direct, high- pressure techniques. In one of the few open-source studies on the effectiveness of military “resistance training,” 58 cadets at the Royal Norwegian Naval Academy were subjected to a simulated prisoner-of-war exercise. Some had received a pre-training experiential exercise in resisting interrogation, others were given only a pre-training lecture. Perhaps of greatest interest is that the use of indirect interrogation techniques significantly reduced the amount of “prisoner” communication confined to name, rank, military number, and date of birth (from 24% to 0% in the lecture group and from 61% to 5% in the experiential pre- training group). More importantly, the indirect strategy (as opposed to a direct one) also increased the percentage of compromising statements revealed by the "prisoners” from 22% to 37% in the lecture group and from 0% to 15% in the experiential pre-training group (Laberg, Eid, Johnsen, Eriksen, and Zachariassen, 2000)."
In short, indirect, non-coercive methods were more effective at getting accurate information.
Edit: it is also worth noting that there are significant downsides to using torture, not the least of which is diminishing our national image around the world. The way we treated detainees at Gitmo has been used as a recruitment tool by anti-American groups in the Middle East, adding to our number of enemies. To use torture is to abandon the moral high ground in a conflict.
Edit 2: if other types of data collection have failed, torture is not going to provide the useful bit of missing Intel. Everything gained through torture is going to need corroboration from more reliable means of Intel gathering, and if those means are already available to be used in a situation, then the torture becomes redundant rather than necessary.