That's true. The book says grease it. If my understanding of this is accurate, the reason is that the specified torque is enough to cause the metal of the nut to flex. The grease prevents thread damage while allowing more turning of the nut before specified torque is reached.Those numbers are with grease applied to the nut.
I don't suppose you know a source for those marking pens? I never thought of that as a reason to re-mark. Basically you can do a visual to check for loosening hardware. :think:It's a good idea to mark the nut position with a marking pen, so that you can quickly see if the wheel has moved after a ride or two.