Surely, I don't need to have my arm cut off to see that it's painful, correct?
In the same manner, one doesn't need to be tortured in order to see the effects on one's patients.
And I'm never saying that torture won't occur, or even that in a miniscule number of cases, it shouldn't. I'm saying that we shouldn't enshrine that capability, to 'enhanced interrogate' anyone, PRECISELY due to reasons like this. If people think waterboarding is ok, but they REALLY want information, then they'll take the next step.
Again, if you knew lives were on the line, what's wrong with REAL torture in the case you cited? What's wrong with pulling off toenails and fingernails, burning the man, or cutting off fingers? I mean, LIVES ARE AT STAKE!
Or is there a line you wouldn't cross either?