The inertia of the platter, the torque available from the motor, the particular musical passage, the position of the stylus on the LP surface relative to the spindle, the cartridge, etc., etc. These are all factors that would influence any measurement of stylus drag. So to begin with, we would all have to agree on one particular LP pressing and on one particular passage on that LP surface. Then, since it is impossible for us all to be using the same cartridge, at least we could agree on one stylus shape for all of us. VTF Also affects friction. These are all things that we would need to agree upon a priori to obtain data that are remotely comparable, and there’s more I haven’t thought of yet. But, Mijostyn, platter inertia is a variable that figures in to the result. Of course it would make a difference, but of course that is what we are looking for.