Thanks Coop. You provided very interesting observations about the listing of varieties. One "professional" can label a coin a "minor" double die, while another can disagree---say with this 1986D penny of mine, for example. That means there is subjectivity in the decision-making---unless the spread and the doubling is so clear that everyone would agree with it being listed as a
DDO or
DDR. I am sure that there are many in the Coin Community who agree with you.
And thanks Silviosi for your comments.