Onhwy61, I also was curious about that same thing, with the points going upside down on the racks and platforms, so I asked about it.
The explanation is that when the points are used upside down on the rack or platform, they are working in conjunction with the platform and another audiopoint in the other orientation directly coupled underneath it, and not in a "stand-alone" configuration.
According to the factory, this changes the behavior of the upside down audiopoint on top, to behave in accordance with the overall system to bring the vibrations downward to mechanical earth ground. It is not done in just a "willy-nilly" or "hopeful" way where they are "guessing" that it will do this. It has been designed by scientific theory, tested, and found to work. That is one of the things that sets Starsound products apart. They are engineered products, and not "garage" products. There are degreed engineers that are producing these designs.
To address your questions about vibrations "back-feeding" up the cones, they do not. The geometry and design of these Audiopoints precludes back-feeding of vibrations, when used in the proper way that is stated in the directions. What will happen though, is that if the entire floor is going up and down, the whole rack will go up and down with it. They can't stop the floor from vibrating, but they will not feed the regular vibrations back up into the equipment. If the floor is that active, then there is a floor problem, not a rack problem. Addressing the floor problem by bracing is the way to attack that, not by compromising the performance of the audio rack. If there is a major floor inadequacy and it is not possible to address it, like in a rental apartment, then maybe the Sistrum products aren't the answer to that. However, in a proper listening environment with a firm floor, they will do better than any de-coupling device.
I might add that the Aurios are not de-coupling devices, but are actually a form of coupling device that uses a ball between the cups that allows lateral vibrations to be dissipated by the minute "rolling of the ball". So you are actually doing some type of coupling right now with your Aurios. But with a different kind of design that may not be as effective as the Audiopoint design. If you like the Aurios, perhaps going further into even better coupling would yield even better results. Just a thought.