MM - speedos have been known to fail also. I was just relating my experience.
As to lubing the cable, WD40 is more of a penetrating oil than a lube. I think they are "lightly" lubed from the factory with some form of graphite grease. Black sticky stuff. Either that or there is a teflon lining in the sheath, because when mine broke, I pulled the cable out of the sheath and got black sticky stuff all over my hands...
The odd part is it actually rusted through a few inches above the drive - where it bends. Now how in the heck does moisture get in a cable like that which is essentially sealed off at both ends?