We seem to see things differently and I don't want to be argumentative, but here are the palces that we differ on.

A shorting ring is purely resistive, no reactance at all. Hence ther can not be any time constants associated with it.

I don't agree that the flux has to be symmetrical for a shorting ring to work. I don't even agree that a symmetrical flux is even necessary at all. Sure if it is symmetrical the second harmonic will be reduced, but the third will go up. I no of no data to show that this is a subjective improvement.

Honestly, from the data that I have virtually all long held beliefe about nonlinear distortion are incorrect. Time will tell.