I did not mean for my post to make waterboarding seem to be simply unpleasant. It is not, it is horrible and inhumane practice whose use cannot be justified.
That being said getting a good scan required me lying on my back holding still as I was slowly lowered into the water. At the end of the scan I had water going into my nose. Holding my breath was unable to prevent this. Certainly not as bad as waterboarding, but certainly enough to elicit a coughing fit.
got it. thanks mate. was an honest question. maybe negligent on my part, but i had something like a dunking booth in mind. wasn't considering a rush up the nose. definitely at least a bit closer to waterboarding than what i'd imagined. :)
if you're interested in hammering out some science for us, waterboard yourself and report back. i think you might be surprised.