Let's be clear here (again). Our government is not allowed to torture. That is the law. Waterboarding is torture. If members of our government wish to authorize torture then they must be prepared to accept the consequences of breaking the law. Whether the technique is effective or not is irrelevant. If they do not wish to take the consequences for authorizing torture then they either refuse to authorize the illegal act, or they get the law changed so that it is no longer illegal.
If I want to drive across the country quickly, doing it at 200 mph in an Indy car would be the best way to do that. But it's illegal so if I do it, I better expect to get pulled over at some point (probably by a helicopter or after I crash). And if I tell Nancy Pelosi I'm going to do it, whether she says it's ok or not, or whether or not she remembers that I told her doesn't matter either. I make the decision and I engage in the act, I'm the one who broke the law, not her.
So stop the whining and get on with the prosecutions.