Doesn't angle of the cantilever change anytime it moves from side to side, meaning, anytime it reads a lateral modulation? Same for up and down and vertical modulation
Also, if the stylus is riding in the groove, reading audible signal, how can it draw a high-amplitude 10 Hz sine wave on top of that? Unless there's sine wave of that amplitude embedded into the groove I can't see how it could do it, there should be no space for the stylus to do that.
At this point I'm even convinced this 10 Hz high-amplitude component isn't really reflecting what is happening in the groove - maybe the tonearm wobbles at 10 Hz relative to the stylus in the groove, and this movement induces current in the cart. Even though we want only current cause my movements of stylus in the groove, we can't get it in isolation, since everything moves and interacts.
Why would we care about pressure on the surface if MM/MC cartridges measure velocity?
Basically you said "it wobbles at 10 Hz and it affects other wobbles at other frequencies". Sorry, but this doesn't seem a convincing scientific argument. In essence this is a statement about a tonearm/cartridge system being a nonlinear signal transducer. 10 Hz affects regions far from 10 Hz. While it makes sense, none of the above explanations say anything about the amount and inner workings of this nonlinear behaviour.
I hope somebody could give an explanation in terms of transducers (I guess cartridge could be called a seismic transducer?)
What you are seeking is a fully developed mathematical model of a highly complex system - I have not seen such a model.
I have seen models that cover specific aspects of the system, and conceptual explanations (like the ones I have posted)
It is a highly complex system, including floor structure, rack/stand mounting (and any isolation/springing involved), turntable feet/suspension, plinth design (layers, materials, absorbance), motor and platter design and mounting, arm type design and mounting - along with any damping involved, then cartridge, cantilever, cantilever suspension and needle. - also lets not forget environmentals, vibrations coming from nearby road, feedback from music being played in the room...
This complexity is part of its fascination - there are an enormous number of variables, and many of us have measured the impact of a whole bunch of these... like any such highly complex system, there are also a huge number of possible "optimal" solutions.
Yes cartridges are transducers... and as anyone knows, transducers are the most imperfect component in any audio chain!
If you want to integrate the various models that have been developed... there are many of us here who would applaud the effort... and would love to use the outcome if successful!