Take a look at this link and let the number of progeny sink in on you for a moment!!
over 17,000 daughters with a WW turned in to the AAA.
Incredible
http://www.blackgrove.com/sires/NBarEmulationEXT.html
My god it's like you people don't have a clue.
Probably the most influential Angus bull of the last 3 decades was the result of a half bro - half sister mating (same sire).
N Bar Emulation EXT. Has probably sired multiple tens of thousands of calves.