Assembly lube and break in oil
You said "I've put together some high dollar stuff ($50k range) this way", so, SOMEBODY has the money to take the chance. I assumed it was your engine, your money. I dont have a crystal ball to know if it is yours or the shop bosses engine, but, hey, if he is comfortable with it, alls good on this end.
If thats what you all want to do, thats cool. I am not one of those people to point a finger and say someone is wrong. Surprised, maybe, wrong...........meh, not my money, I dont care. All I know is, for me, short of spinning the crank to check timing with a ratchet, my engines are getting primed before cranking and or starting.

