I've read repeatedly that dipping the length of case to be annealer in motor oil emeaditly prior to immersing it in molten lead is how you prevent any lead from sticking to the brass. Is this correct?
Yes, but not just any oil.
It has to be Mobil1 synthetic. No other, not even Amsoil.
This will not burn off until pooling to a sort of critical mass on the molten lead surface. It's a slow burn, no big deal, and useful to remove the oil. Of course it's done outdoors, but there is no lead in the fumes at process annealing temperatures. The hazards in fumes are from impurities present, like smoking oil, zinc, silver, etc.
The salt used for annealing of brass melts below 300degF:
Salt – Ballistic Recreations- Essentials For Salt Bath Annealing
Just pay attention & don't drop anything in either lead or salt baths. But if you do, it won't kill you.
Tipping the bath onto your penis might(unless you're Chuck Norris).
I've done lead dip for ~25yrs now. Will probably try salt & see how well it works.
Unlike any torch or inductive process, you can do deep case annealing with dipping and without threat to webs. I hold case heads with my fingers while dipping, and drop in water. As long as the brass is not held(for quite a while) at 450degF, it's grain structure does not change.
With dipping you have such precise control over temperature that there is just no reasonable way to screw it up.
As to the of paranoia in murmurs of the ignorant;
Pay it no mind