I'm a noob when it comes to errors and doubling, so please excuse me if this is a stupid question. Is the activity on "E Pluribus Unum" mechanical doubling? Or is it even possible to tell from the photo? I looked in the Cherrypickers' Guide and didn't see any doubled die reverses for this date (1941-P).
I would say any doubling you see is caused by die deterioration. The metal is pushed towards the rim causing those fine lines on the surface of the fields.