I'm 99% sure that is the type of doubling you get when you have MD on incuse design elements. EDIT: http://www.error-ref.com/incused-machine-doubling/
You can definetly tell that set of dies has their glory days if marriage well behind them. I would agree with the machine (incuse) doubling and also would add mid-late die state, the deterioration. You can see where the high points are getting mushy and the die wear is obvious. Nothing is really consistent. But regardless, its unique and really cool. One day everyone will realise that these coins are actually more rare than that of the coins attributed to a specific die marriage. Relatively speaking when your referring to the deterioration of a specific sets of die, Very few coins are exactly the same.
The doubling may look good but what needs to be present is doubling on the raised devices that are not MD or worthless doubling. I think some more photos of the whole coin are needed.
It has been said that it is not impossible to have a doubled die on incuse lettering. I have read that page many of times. I also have studied these new quarters since they came out. The only thing that is separating most of these coins is central doubling. And further evidence of a Doubled Die. If there is no other evidence on the raised devices then it surely is Incuse Die Doubling.
