Not sure of the mechanism in the RCBS lockout die, but I ALWAYS use one and it has saved my bacon two or three times in the 25,000 or so rounds I've reloaded. That shows how often I've actually needed it, but those 2 or 3 errors could have been the fatal ones.
Smart Gun + 1 Battery + 3 Wires = Dumb Gun
PC = Agenda driven groupthink filter on reality.
Apostrophes denote ownership or missing letters NOT plurals!