From your link (actually I had to go seek the story myself because your link is the url to the last page and I couldn't get to the first page from there:
How a Detainee Became An Asset
Sept. 11 Plotter Cooperated After Waterboarding
By Peter Finn, Joby Warrick and Julie Tate
Washington Post Staff Writers
Saturday, August 29, 2009
Mohammed, in statements to the International Committee of the Red Cross, said some of the information he provided was untrue.
"During the harshest period of my interrogation I gave a lot of false information in order to satisfy what I believed the interrogators wished to hear in order to make the ill-treatment stop. I later told interrogators that their methods were stupid and counterproductive. I'm sure that the false information I was forced to invent in order to make the ill-treatment stop wasted a lot of their time," he said.
Critics say waterboarding and other harsh methods are unacceptable regardless of their results, and those with detailed knowledge of the CIA's program say the existing assessments offer no scientific basis to draw conclusions about effectiveness.