Well, gosh, if the people asked to find a legal rationale for torture somehow managed to place waterboarding in a legal not-torture box, then that's all that need be said. Why are we wasting time talking about moral and ethical issues at all, when the lawyers, hired by the people who wanted to torture detainees, found that, yes, you can do so, have spoken.
You've got to be joking citing those two as evidence for anything.
And I'll just note that you're all too willing to stridently disregard reasoned legal opinions of SC justices, but only when they don't come to conclusions you like, so I have no idea why you think this kind of argument is persuasive, especially in this context. Take any abuse of civil liberties or act of evil by ANY government. Almost by definition the abuse was placed into a box that made it "legal" at the time and place. We could quickly list 100 examples, here and abroad of "legal' but evil or morally repugnant acts.
Bottom line is anyone with a loved one subjected to what Yoo and Bybee concluded was legal not-torture is lying or very adept at self delusion if they say they'd conclude their loved one was subjected to legitimate interrogation techniques and that the interrogators would be justified in relying on a single admission by them during or after they were tortured/subjected to EIT. If you were waterboarded and believed it would stop the waterboarding, you and me and everyone here would admit to ANYTHING - that you were a space alien from another planet, a secret spy for Putin, a FDR's reincarnated dog, whatever. That's what torture does. You don't get those kinds of guaranteed results from any kind of legitimate "interrogation."