Just caused by a worn deteriorating die. Not a doubled die and is not worth much (if anything) as an error. That coin is known as a "Poor Mans Doubled Die" even though it is completely unrelated to a doubled die at all.
Here is how a real doubled die should look, notice how raised the doubling is?? It's not flat and ghostlike and is almost a part of the original lettering.
For the sake of fairness it should be noted that there are other 1955 DDOs besides the "big one", but with that said, I cannot see the coin well enough to say one way or the other.
