I also suspect the platter is light, perhaps very light, in order to minimize the magnetic field requirements. I also don’t think that some motion of the platter during play is necessarily a bad thing. The primary advantage of isolating the platter is the attenuation of structural vibrations in the frequency range that could excite the resonant frequency of the cartridge (and tonearm). Thus, low frequency motion of the platter, even visible motion, would be relatively innocuous as far as SQ goes since those very low frequencies are well below the 10-12 Hz resonant frequencies of the cartridge and tonearm. And they would be well below audio frequencies
Geoff, that is true but any extra motion is not ideal. Since there is no spindle how accurately does it spin in one location? Does the platter always align to the same spot? If not this could change the pivot to spindle difference each time. When aligning a cartridge with the platter at rest, will it float in the exact same horizontal location as it does when resting? That could cause an alignment problem. This design may help one design problem but it also creates new design problems as well.
On that same track, in order to align the cartridge correctly you would need to put blocks under the platter to raise it to the same height as when it is spinning. How would you accurately place the platter at the same place it spins when floating? That would be very difficult it not impossible.

On that same track, in order to align the cartridge correctly you would need to put blocks under the platter to raise it to the same height as when it is spinning.

the website discusses the feet which are automatically raised when the table is not used.  here is the video from the site.  

https://ksr-video.imgix.net/assets/014/328/049/8218e7bfb759b4b621a7a1c4329db837_h264_high.mp4
Ok thanks. I missed that. There is some sort of groove on the bottom of the platter. The feet look like they are cone shaped to fit that groove.