I saved this from circulation 22July15 but found some odd doubling about 4 days ago. It's a 2001-D Rhode Island State quarter with doubling under the bridge in 4 places. Since single-squeeze die production kinda eliminated classic doubling I was surprised to see this because it really shouldn't be there: Here's a better pic of the left span... So is this some kind of design creep or die stutter? Anyone know what this really is? Any help would be appreciated...Spark.