From 2005 Robert Harris reported:
"King Kong was a victim of its own success... The large number of prints... manufactured... probably wore out Kong's negative. The earliest surviving material on Kong is a master positive made from the camera negative in 1942. This print was the backbone Richard...
I've done some comparisons between the blu and the dvd and the blu has various darker scenes--on the island--I was surprised by this--I have to assume WB is aware of this--and went in that direction.
I also did the same procedure on son and MJY---those 2 titles matched exactly in video levels.