Ok this one looks hard and no havent learned what a DD is yet. Yes this is most likely MD, but a girl can ask.again.
I'm not as familiar with IHCs, but I did learn a few weeks back about Longacre Doubling. This may be that. http://www.error-ref.com/longacre-s-doubling/
wow, nice photos. Some die deterioration, coupled with slight MD, thats my opinion. Gary in Washington