On the 2016 what your are seeing are marks from Machine Doubling called striation lines. When the die slid, it left these lines from the metal movement. They are the edge of the dies devices that show the sharpness of the die on those devices on the die. Something you can try at home is using a kitchen paring knife and s soft stick of butter. Hold the knifes edge vertical and slide it carefully across the top of the butter. Note the lines that are left? Those show the edge of the metal of the sharpening of the knife. But that is what they look like. Other examples:
There is not premium for these, just an explanation of what they are. They are not a doubled die, just metal movement during/after the strike from Machine Doubling that leaves its fingerprints behind so the detectives can figure out what happened.