There are different factors for distorting the design on a coin. The first is strike error. The movement of the die during striking with the coin held fast with the collar creating Machine/mechanical doubling. That is probably the biggest question asked along with plating sliding from the strike creating a false line. There is a third issue relating to striking that sometimes come into play with dies. As the get older the outside edges of devices start a wear pattern. Sometimes after the very late die state (VLDS) is reached the detail from the die edges of the devices start wearing so the edges of the devices and the fields start to snow drift over each other. In other wards the details get weaker and weaker leaving die wear patterns on the devices. This is even strong on the devices that face the rim of the coin. Making a false "SO Called" Doubled die. The 1955 "Poor Mans Doubled Die" is part of that problem. the outside devices wear causing the die to flow even stronger to the fields. It can even be seen as wear lines that rise up on the other edge of the devices. This beyond the flow lines that also flow toward the rim. So what you might be seeing the the
Die Deterioration from wear. Common on coins and not extra premium (Even on the Poor Mans so called doubled dies) because this is just wear and not a variety created on the die. Kind of "Newbie" stuff that we all have to learn to be able to tell what is worth keeping and what is to be tossed back into circulation for the next "Newbie" to find. Hope this helps.