I definitely agree with you point, but I think that's what I'm wondering about? Can it actually be filtered out, and are tracking companies actually do this in practice, or is it like when someone says they bridge an airgap by making two computer's RF spectrum do funny things? Possible in a lab, yes. Something most people need to worry about? No.

I'm not saying this _isn't_ the case for tracking -- I just don't have much of a way to know what techniques are actually being employed in real life.