Many thanks for your vote of confidence, re the quality of my analysis. Out of interest, I am an engineering psychologist by profession, and so, perhaps, am used to engaging in detailed, often convoluted, analytical discussions on complex technical issues (usually about the operation of commercial nuclear reactors)!
One further note on the tone arm 'goodness' topic is that, even assuming that all manufacturers aim to develop an arm that least interferes with process of 'reading a record', the innevitable use of different materials, in unique combinations, will, by definition, directly impact on the performance of the whole unit in unique, and often in subtle, or, sometimes, not so subtle ways. Thus, all arms must, by definition, sound different from one another. Of course, the rub is whether, as individuals, we find one set of 'compromises' more acceptable/truthful, than those of another design (which, in turn, is a function of our individual sensitivity to various types of distortion of the musical signal).
The important point is that no manufacturer, no matter how much money they may spend on exotic materials and techniques, can ultimately defy the laws of physics. All design in this sense is, and must be, a compromise (which is something we all ought to bear in mind when in our persuit of excellence). The question is, how much of a compromise, and how much more are we willing to pay to minimise those behaviours that interefere least with the function of extracting information from a record, and/or irritate our musical sensibilities? For some, the depth of our pockets define the second aspect, but as the Rega RB300 shows, just because you may not be able to afford much, does not necessarily mean that the compromises have to be either large, or unacceptable. Indeed, the really clever thing about the RB300 is that it achieves such a good balance at a such a remarkably low cost!
Obviously, in discussing the above, we find ourselves sailing perilously close to the boundary of another, somewhat thornier issue, which is whether different is necessarily better. But that is another story! Anyone else care to comment, here?