We see many forks/headsets dry of any lube but what came in the actual bearing from it's original manufacturer. We usually open them up because of complaints of clicks and creaks. Often the bearings are still in good condition (although some are so rusted...) and only a need of cleaning the mating surfaces and applying a film of grease during reassembly. But without taking the time and effort to take things apart no real understanding, WRT condition, can be made. Additionally there are bearing "cartridges" which are just preassembled cup and cone designs with none of the nicer features of what many will think of "sealed bearing". These bearings can be easily separated into their inner, outer and rolling elements with only a knife to pry off the seals. So even a manufacturer's claim of sealed bearings isn't a complete understanding without further info or investigation. Andy.