But; I never saw any KEFs or Lowthers, in the shoppe, so- what do I know?You don’t. So I’m telling you.
Search yourself (just Google "rotating speaker drivers") plenty to read.
Many very tight magnet to coil gap drivers or heavy coned ones also, that sound like their polling, "can" be fixed just by a 180 degree rotation.
Other ones I remember that sagged, were the 1st model Reference 3A De-Capo and the bass driver in the bigger old Klipsch. La-Scala, Horn etc
Cheers George