To keep this on track, Halcro, did you use a torque wrench on your cartridge screws? The tension on cartridge screws can certainly affect sonics, for all the reasons you and others reiterate. If one were to draw conclusions regarding the efficacy of this or that fastener per se, then I think torque has to be a constant.
You're quite right Lewm....
Here's what Dietrich recommends:-
If you happen to have a small torque driver to use, the set value to use (ONLY with our cartridges, as they do feature a thread in Timet 1100 material!!) is: maximum 0.85 Nm with M2.5.
Unfortunately......I don't possess a small torque driver so I had to just use the Allen Key supplied with the screws and was careful not to over-tighten 👀
After hearing the results with the Timet screws though.....I might invest in a torque-driver.
Interestingly....in the latest TAS, there is a review of the latest Brinkmann Spyder turntable where the Reviewer comments:-
Like many designers, Brinkmann prides himself on using subjective evaluations.
"Everything has an influence on sound", he writes. "And we have to accept that these influences are real - even if (for the moment at least) we have no scientific explanation. Each single part of the device, no matter how trivial, has an influence on sound. Yes, even the smallest screw"
Through careful listening tests he discovered that replacing one of the stainless screws that affix the cantilever in the Pi pickup with a titanium brought "sound that resembled the original most closely"
We appear to be learning more about vinyl reproduction....and at a faster rate....than even the great engineers and designers in the 'Golden Age' could have imagined 🤓