Agree, I doubt the factory faffed about.
I use plenty of oil during assembly then fill thru the rocker box which ought to drown everything but not too much in the tank..a few kicks to move it around the pump, fit the plugs and fingers crossed.....always find oil back in the tank after a few seconds, and even if it takes a while its no detriment with the amount of oil that's sloshing around anyway if you've given it a good fill up.The Penrite lube sounds like a good idea though.