If you look at biathlon shooters and smallbore shooters = they all retain the classic chicken wings. You will not see any of them drop that elbow. Marines are taught that way to this day. A good thing lasts a very long time and that chicken-wing elbow is one of those.lee marvin, also a marine, fired his rifle the same way in the movie "death hunt" . the rifle was a 30/40 krag though. i didnt know hackman was a marine, he was an incredible actor though. he could play a good guy or a bad guy equally well.
There is more science to the chicken-wing than meets the eye. Maybe someone can shine light into its purpose and how it improves rifle marksmanship.