It seems that swinging the compass should be done with the electrical system dead and the radios off, that is when I'd want the most accurate magnetic compass.
Why do you want your compass to be most accurate when your airplane isn't being used?

I think he means that when all the electrical systems (& DG) go south
but you're still "up there, wishing you were down here", is when you
want the mag compass to be dead on.

Jose
--
The monkey turns the crank and thinks he's making the music.
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