I'm not an EE but do have more involvement with mechanical concerns relating to TT's, I have always been fortunate to have adequate EE support when required, as well as, at times be steered by those with much better mechanical knowledge than my own.
My first experience of a TT's Platter Bearing undergoing a upgrade treatment in place of the manufacturers version has been over 25 years ago on a Idler Drive TT.
Measurements were not required at this time or any other time since to show why a change made to a mechanical interface has been for the better or worse.
Changes to mechanical interfaces have for myself, been able to present a detectable change, in nearly all cases one that is audible, a change that is effecting the voicing of the sound being produced, usually, one that allow more of the sound to be presented with a perceivable less loss.
When working with the Lenco TT's, a PTP Chassis version of a Lenco, does have significant improvements where the end voicing for the produced sound is concerned, especially when compared to a typical design for the chassis mounted bearing and motor.
A modified typical chassis on a Lenco, the type that has the typical chassis cut to produce the circumference pressing of the chassis form only, and then interfenece fit pressing the chassis circumference form into a rebate on a Plinth, is as a modification very closely resembling the PTP version of the Lenco.
Differentiating these two methods is not as easy as differentiating the sound being produced from the typical chassis design.
Measurements have not been required to reinforce the notion differences are detectable
Experiencing Work that has been undertaken with the Bearing Housing on a selection of different drive TT's, has also produced assemblies with alternate materials in use to the original, that have had very impressive impact on the sound being produced. For myself no measurements have been required to be taken to reinforce what has been detected as a valuable audible presence.
Changing materials used for the Plinths on a TT, as a result of my experiences of doing this, has also produced quite noticeable changes to the voicing of the sound being produced.
I have not used measurements to reinforce my experiences, but have seen measurements for a variety of materials that show some of my choices for a material will be a superior option.
I have for many years, pretty much since first discovering the Dr Kaneta design for the SP10 MkII, viewed the PTP and Kaneta and later Variants discovered as a similarity in design concept, being not too far apart in their design intent.
As a mechanical interface the SP10 MkII and now seen 1200G Spindles Bearing Housing and Motor, will in my assessment as a result of past experiences, benefit from being removed from the original chassis, where the new fitting to the support structure will be a low friction interference fit, with the TT's metal casting contained / bedded into a accurately dimensioned rebated material functioning as the chassis / plinth.
This method, will in my view, has potential to add to the quality of the sound being produced, and create a voicing that has a further attraction. There are other designers selling commercial products for substantial monies, having adopted similar mounting methodologies.
I can't see how a measurement of such a set up will reinforce my assessment of the sound being produced.
I am always keen to learn where a Electrical Improvement can be found as a betterment, I have access to individuals who are quire happy to discuss the concepts put on the table, hence my introducing the 1200G with an alternative mounting and Power Supply to these individuals as well as the forum.