A "scientific" approach is only possible if you have a calibrated instrument that does the listening itself. Which of course is not going to fly. In the end, we are stuck with subjective impressions.
Yes, I think this sums it up nicely, which is why I was interested in hearing other peoples' experiences with various tonearms, as theory can only take us so far. As I listen to more tonearms, I will add to this thread in a more meaningful manner, but I'll probably try one new tonearm every year or two, so my input will be rather minimal.
I think @pindac is our resident quantum philosopher to whom all things are possible at all times, but only if not directly observed. . . 😉