I found this excerpt from the Congressional Record on an anti-war site under the title, Senator Whitehouse on Torture: It’s Worse Than Everybody Thinks.

[Congressional Record: June 9, 2009 (Senate)] [Page S6359-S6361]

As recently as May 10, our former Vice President went on a television
show to relate that the interrogation process we had in place produced
from certain key individuals, such as Abu Zubaida–he named him
specifically–actionable information. Well, we had a hearing inquiring
into that, and we produced the testimony of the FBI agent who actually
conducted those interrogations.
Here is what happened. Abu Zubaida was injured in a firefight and
captured in Afghanistan. He was flown to an undisclosed location for
interrogation. The first round of interrogation conducted
professionally by Soufan and his assistant from the CIA produced such
significant intelligence information that a jet with doctors on it was
scrambled from Langley–from this area–and flown to the undisclosed
location so that the best medical care could be provided to Abu Zubaida
so he could continue to talk. That was the first round of information.

In the second interrogation, conducted consistent with professional
interrogation techniques, Abu Zubaida disclosed that the mastermind of
the 9/11 attacks was Khalid Shaik Mohammed. That may be the apex piece of
intelligence information we have obtained during the course of the
conflict.

At that point, the private contractors arrived, and for some reason
Abu Zubaida was handed over to them so they could apply their enhanced
interrogation techniques. Ali Soufan testified that at that point they
got no further information. What triggered the first round of
information was that Soufan knew about Zubaida’s pet name that his
mother used for him. When he used that nickname, Zubaida fell apart. He
didn’t know how to defend himself, and he began to disclose this very
important information.

Knowledge, outwitting people, playing on mental weaknesses, taking
advantage of our skills as Americans–that is what worked and got the
information about Mohammed. He was

[[Page S6361]]

turned over to the private contractors for enhanced techniques and they
got nothing.

It was then determined that because the interrogation had become
unproductive, he should be returned to the FBI agent and CIA agent who
had twice interrogated him. It was in the third round that he disclosed
information about Jose Padilla, the so-called dirty bomber, which was
so important that Attorney General Ashcroft held a press conference, I
believe in Moscow, to celebrate the discovery of this information.
Again, for some reason, he was turned back again to the private
contractors for the application of more abusive techniques, and again
the flow of information stopped.

For a third time, he was returned to the FBI and CIA agents again for
professional interrogation, but by now he had been so compromised by
the techniques, even they were unsuccessful in getting further
information.

As best as I have been able to determine, for the remaining sessions
of 83 waterboardings that have been disclosed as being associated with
this interrogation, no further actionable information was obtained. Yet
the story has been exactly the opposite. The story over and over has
been that once you got these guys out of the hands of the FBI and the
military amateurs and into the hands of the trained CIA professionals,
who can use the tougher techniques, that is when you get the
information. In this case, at least, the exact opposite was the truth,
and this was a case cited by the Vice President by name.

You might want to compare this information with Torture debate: conducted by Christine Amanpour on CNN.