I got to talk to a real honest to goodness tribologist. I was also asking about moly and corrosion. He said, depending upon the formulation, that commonly used moly can cause some very bad copper corrosion values of well over 3b. This is especially true of moly additives added to the oil as an aftermarket supplement. He also said that a tweak of the additives can prevent moly corrosion without effecting the positive moly properties like FM/AW, and that moly was also an antioxidant.
That is why I never add anything to the oil and am very leery about mixing oils with different add packages, especially percentages of additives.