Buzz, let me see if I can crystalize my thought here. In reference to Aconcagua, you stated that the climbing is easy.
(Yes, relatively so, but surface conditions can change pretty rapidly up there.)
You stated that the danger on this mountain is the camping.
(That's a pretty silly statement, if you think about it.)
If spending nights up high is what makes you sick, tired, and dehydrated, then you are doing several things wrong.
What I think maybe you meant was that the danger on this mountain is in sleeping overnight. If you are going up so terribly fast as you were, then spending a night up very high would be dangerous. However, that kind of a stunt is done successfully by only a tiny percentage of people who go there. In other words, if you are a "Viesturs" kind of guy, then I say "more power to you." However, for the remaining 99% of us, doing the rush ascent like that is extremely risky, at least from a medical risk point of view.
It has often been said that most of the severe forms of high altitude illness take 12-24 hours to set in, and they take at least 24-36 hours to become fatal. I think your strategy was to run up and down the mountain and escape before the bad problems could set in. I've only done a little of that myself, but never this seriously, and never this high. I mean, the summit is approximately 80% the height of Everest, so it is a no-fooling-around mountain.
Despite all of this, there are some forms of high-altitude illness that can be fatal in single-digit hours (ex., HACE). If you had the bad luck to get hit with something like this when you were topping out on the Canaleta, rescue would be almost impossible, and fatal consequences follow. I've been up on high mountains before when climbers got sick like that, and I would personally strive to avoid those situations as much as possible.
So, I suspect that you ought to get tested by some physiology lab. Maybe you have the same genes as Ed Viesturs. If so, that would explain a few things. The rest of us mortals may have to continue to plod up the big peaks in the traditional fashion or else risk meeting our Maker.