Stefan,

Because of the way a compass is mounted, it will briefly tend to
continue moving after a turn.

Yes. So?

Um... no! The compass does not "briefly tend to continue moving after a
turn" but it has a well defined turn error,


Please! Not you, too! Your "well defined turn error" does indeed lead to
the fact that the compass "willbriefly tend to continue moving after a
turn." Which is why I said yes to affirm that statement.

--
Thomas Borchert (EDDH)