Isolating the turntable system from external and airborne vibrations is certainly essential. That creates one point of vibration attenuation and frequency reassignment from external influences.
A lot of the above discussions seem to bear on the issue of the various interfaces of the vibration detection system, itself and how they "drain" into this interface between the turntable system and the outside "world".
For instance, a theoretically perfect rotating platter with a perfect gravitational field on a perfectly frictionless air or magnetic bearing creates another point of isolation within the turntable system itself. Also, the more frictionless the bearing, the cartridge modulations and imperfections of the vinyl will create centripetal and centrifugal de-stabilization effects over time which can only be reflected back into the vinyl/cartridge system from the platter to the cartridge. I imagine this is why the Caliburn system unloads the mass but preserves a mechanical interface, to stabilize this interface and create a point of vibration drainage apart from the cartridge interface, itself.
Also, a linear air bearing tone arm, also theoretically frictionless, creates another point of isolation from the internal interfaces of the turntable system. Although this may minimize tracing distortion, it creates two different effective masses and another isolated vibration interface. Unless the damping from this system is perfect, the cartridge sees reflected vibrations from the tone arm system itself without an external source of vibration drainage. Also, if the friction is theoretically zero in some dimensions, the cartridge is free to wag the tone arm without inhibition and is not restrained around the groove modulation. So this system is not restrained or drained as with a mechanical inerface.
If you have an air bearing platter AND an air bearing tonearm, you have two theoretically frictionless points of isolation mediated by the cartridge interface. This seems like you have one tail (the cartridge) wagging two dogs (platter and tonearm) against two points of isolation without drainage, relying on perfect damping from the two points of isolation. I don't really see how this is ideal even in theory.
Also, on SME website, they cite that material density and stiffness are at least as important as sheer mass. The SME tables create a "mass effect" by using stiff, high density horizontal plates and turntable platter rather than sheer mass.
