Cuddly, torture works wonderfully when conducted properly by people who can analyze the information. Simply put you don't like the idea, a lot of people don't, but history has never shown that it doesn't work, quite the opposite. This is why it's a "human rights" issue and there wouldn't be a demand to use it if it wasn't reliable.
The thing is that when conducting a proper "hard" interrogation you are going to have people handy with an idea of the whole situation to put what is extracted into context, not sitting there simply accepting anything the guy tells you.
As far as the admissability, well the entire point is to bypass the legal system and give groups like the CIA a free hand when it comes to intenational issues.
Other than personally not liking it, really there isn't much you can say about it.
As far as the "failure" of things like Gitmo and the like, they failed because they were under public scrutiny and had people crawling all over them, making cases based on the existing laws/standards. Had we changed those laws/standards and kept the public from being involved at all, then it would have been something entirely differant.
Had we conducted outselves more efficiently and not held back due to moral kid gloves (our own society fighting itself effectively) we probably would have nailed Bin Ladin and Omar.
Though admittedly when it comes to Mullah Omar it's more of a touchy subject. We actually had every reason to believe that he (and the Taliban) would support us against Al Queda once they struck against the US since we pretty much gave them control of Afghanistan by helping them force out the Russians, and taking the pro-USSR faction (now the "Northern Alliance") out of the picture.
Honestly, had we simply blitzed Afghanistan unannounced we could have accomplished a lot, but that relies on Hindsight, and I really can't blame the goverment for thinking that Omar would have backed us and leading diplomatically.
At any rate we're going to have to agree to disagree, I don't see us having a meeting of the minds on this paticular issue.