Sorry Ray but I think you might have misunderstood what I meant.
You are right that Witnesses take the blood policy seriously and often make a stand almost as a reflex action. In these circumstances however what is really happening is that the Witness is making a stand for whatever the FDS have said is currently acceptable and not acceptable. They don't make logical and conscience driven decisions based on their own understanding and research.
If the FDS change their mind then so too the mind and conscience of the majority changes. This is where my comment comes in.
If the FDS ever further reduced the scope of the prohibition or even removed it then my money would be on the R&F simply following them and accepting the new scope. They would all take whatever if the WTS said it was now ok.
I have to say I don't see the WTS removing the prohibition completely as the legal exposure is probably scaring them.
As has been pointed out in another thread the whole blood situation is far more about organisation policy management than a truly theological position based on honest and conscience driven interpretation.