411
The silenced-rattle you refer to is a much rarer phenomena and somewhat unique with engines that normally tinkle or rattle why windmilling on the ground. It's called blade lockup which is a stick/slip sliding friction of the snubbers/clappers that has forgot how to slip at low RPM.
Anthony
The bearings in engines can run damn near forever on the little oil that's left in them at windmill speeds. They only need the oil quantity that you decribe at highly loaded conditions.