Many thanks for these links @Tarrant1702 
Fortunately, physics are the same this side of the event horizon 
Stefan made a really nice explanation of the basic principles and supports that really nicely through his experiments. He nailed it when he wrote that the de-coupling provided by the vibration insulation reduces the stresses on the printer frame’s, thereby improving print performance. That would also apply to a Core XY, but with a somewhat higher internal stiffness.
Tom’s observations are (almost) also in line with Stefans.
My very simple modelling only considers the printer as a single rigid block, as I was focussing on the vibrations transmitted to the supporting surface. Same thing and principle, but they both also assessed the internal system response very nicely.
The reason Tom’s hanging printer did not work as intended is that he inadvertently did not build a vibration isolator. By hanging the printer from the top, rather than hanging a platform on which the printer stood, he actually built a double pendulum. That is also called a Chaos Pendulum. 
It may at first be surprising that his paver experiment did not achieve the same kind of results as Stefan’s. However, Stefan nicely worked out that thick pads are needed. Tom’s set-up with the paver and thin feet looked rather rigid, so only a small difference can be expected due to lack of moveability of the entire system against the surface.