2014-P Jefferson Nickel: DDD Optical Illusion Of Notching.

Very interesting. Thank you for sharing!

I don't think this is Machine Doubling. You can see the surface metal flow grains in the fields. The feathering from the bottom of the devices is from the eroding of the incuse die features towards the rim. Those light lines around the letters have almost no depth, it's really just the Die Deterioration causing a different texture on the coin surface, which reflects the light a little differently.

I've looked at thousands of current model nickels at this point, and I actually don't remember seeing much Machine Doubling. On older coins, particularly 1950-1969, I would say Machine Doubling happens way more often. Current nickels seem to suffer mostly from Die Deterioration.

That's just my Two Cents, of course. I would be interested to see some current model nickels with MD.

anything with sharp notches to my way of thinking argues against Die Deterioration because wear is mostly a random process with a net smoothing effect

think about a coin worn from circulation, the devices tend to soften and round rather than develop sharp outlines

the die wearing process does have some feedback, hence the orange peel appearance that reinforces itself in a manner similar to a mogul field on a ski slope, but that too is otherwise unpredictably random