Jim Kelley wrote:
. . .
Mixing on the other hand is the product (rather than the sum) of two or
more waveforms and does in fact yield different rotational speeds.

And multiplying voltage and current waveforms, or squaring a voltage or
current waveform to get power gives a wave with double the rotational
speed and, unless V and I are in quadrature, a DC offset.

Roy Lewallen, W7EL