Marc Theissen has written several times debunking this fallacy. The EITs were not to extract information but to break the suspect's will to resist. The questions they were asked under duress were ones to which the interrogators already knew the answer. Once the terrorists will was broken, information was extracted using conventional techniques.
Now there is a credible independent expert on the subject for you. /I hope I don't have to point out the sarcasm in this statement/
The guy is a speachwriter and republican political operative with no experience in national security, intelligence, or investigative techniques.
And why real conservatives would choose to defend the bigotted ignorant actions of know-it-all better-than-anyone-else neocons is absolutely beyond me. Remember, these guys bankrupted the US.