Pros and Cons of Platter Mass

In my opinion, the platter, spindle, and bearing with or without thrust pad form a closed system in the sense that they are carefully engineered to work well together in a well designed turntable. Therefore I would be loathe to do anything to dramatically alter platter mass or the materials used at the bearing/thrust pad interface, or even the lubricant, without considering the effects on the other constituents of the closed system.

I would be loathe to do anything to dramatically alter platter mass or the materials used at the bearing/thrust pad interface, or even the lubricant, without conside   ring the effects on the other constituents of the closed system.

I wish more folk would heed this sage advice.

I have seen a number of Garrard 301/401 TT's with aftermarket thrustpads/balls that have damaged/worn the spindle.
I have seen many TT's with accelerated bearing wear from using "better" oil.

Peripheral Rings and Puck Weights are a common used method, and when used are adding mass, where the Peripheral Ring has the added effect to increase inertia.
Each of these ancillaries when in use, add weight to the Platter and increase on the load being applied to the Spindle and Interfaces.  
I am not aware of any TT Producers putting forward disclaimers that advise against the use of such ancillaries. These ancillaries are commonly accepted as methods to be used to Clamp a LP to a Platter.

To date I have not seen any reports that suggest a detrimental outcome to a Bearing Assembly has occurred as a result of these ancillaries being used.  There may be others that know a different outcome.
   

Never understood the idea of using a hard thrust pad. Any mechanical engineer is taught that one surface of a plain bearing should be hard and the other sacrificial surface should be soft. Hardened steel shaft running in soft bronze bearings or a very common usage is in engine bearings, a bearing shell with layers of material that can be scratched with a finger nail that runs against a steel or cast iron crank pin. As long as there is a film of oil between the surfaces than no wear will occur.
Wear should always take place in the softer sacrificial material.
A time proven design for a turntable thrust bearing is a steel ball at the bottom of the spindle and a Delrin thrust pad. I have used it in my rebuilds and the Delrin seems to hold up very well with no wear on the steel ball.
My lubrication of choice is a light hydraulic oil, usually AW-32. I don't use engine oil, it has tons of additives, most not useful in a TT spindle at all. Any of the oils that have particles added and being touted as some kind of "super lube" have no place in a TT as well.
I don't understand the folks that think they will gain something by using some kind of magic oil, this stuff has been understood for well over a century and is proven. Most commercial TT oils are either a light hydraulic oil or very similar. Most general lubricants that you purchase in a hardware store are again just hydraulic oil.
Turntable manufactures don't have a tribologist on staff to formulate oil, they will look at the engineering specs on the oils available and choose one, mostly it's just hydraulic oil. This isn't rocket science.
BillWojo