Firstly Welcome to CCF! I personally do not see any doubling, but a quick check on Wexler's site shows 48 different varieties of DDO for the 1970 S. I am far from being an expert on this matter but I would hang tight and wait for someone more knowledgeable on the subject to pipe in. You should also go to the DDO listings section of http://www.doubleddie.com and see all the different varieties of the 1970 S. It's definitely worth checking out. Good luck.
























