This is machine doubling, not a doubled die. You can tell because both the mintmark and the date are doubled in the same direction, which is a good indication of machine doubling. Keep up the hunt! Here is a link to a thread I posted on a doubled die I recently got. Notice the "notching" and fullness of the letters. The doubling is not flat and shelf-like on a true doubled die. I would recommend purchasing a cheap 1995 DDO to help understand the differences. They are inexpensive and easy to come by. Best of luck! http://www.cointalk.com/t217960/
Not sure what an mddo is. You can either have MD, or a DDO. An MDDO would imply a machine doubled die, which doesn't make any sense. 1968 and 1969 are well-known for having machine doubling.
