Magnetization & Demagnetization any conclusions?

If there really is a random magnetic field in the LP, it will manifest as noise as the magnetic field is moved past the MC cartridge, much like tape hiss as tape moves past a tape head.

However it will be at a much lower level! So if y'all are hearing a reduced background noise after treatment, I would give the magnetic field idea some credence.

The only problem is, static charges will be interpreted by the cartridges as random changes in voltage (IOW, noise) as well! I would expect wood and plastic body cartridges to be more susceptible... Interesting topic. I don't have any sort of instrumentation that I would deem sensitive enough to sort any of this out, so for me it remains an intellectual challenge; apparently one that is audible. Sheesh.

Why not support the arm so that the stylus is just out of contact with the LP. Turn up the volume, and what do you hear? Probably a little noise. Now start the platter. What do you hear? If the noise doesn't change the LP is not magnetized.

That is how I would describe it. Lower noise floor which allows one to better hear separation of the notes and stuff. This is definitely in the realm of insanity and one will get much more of an impact by properly cleaning their records. But I find the 10 or 15 seconds it takes is worth it, and I have yet to find a record that needs an additional treatment. Nor do I find any difference in static behaviors. I.e., I still have to use my zerostat gun.

Good answer, eld.
If the LP were magnetic/magnetized/paramagnetic or whatever, it'd induce a current in the cart if moving relative TOO the cart.
Even a paramagnetic material should show this property.

If something induces a current one could probably hear it, especially with a low output cart. I don't think lifting the motor at least a quarter of an inch above the lp is going to show much of anything as far as the tiny magnetic fields that these appear to be. Static, on the other hand, has been known to induce snaps and pops with an arm still on the rest. But that is built up potential that wants to jump to equilibrium. I don't know if this "technique" is actually removing magnetism or just causing them to orient differently.

I seem to recall that someone did try to measure this. Maybe it was soon after Fremer's article, I'll see if I can find it.