TD they will never change the blood doctrine. The amount of people who would sue them for the wrongful deaths of their loved ones would be astounding.
Aside from your perfect explanation, let's also look at Pauls' words when he said (I apologise for not quoting the scripture exactly as I have a headache and cannot be bothered to look it up right now) that the law exists for the sake of man and not man for the sake of the law.
The blood stance puts the law ahead of that which it's supposed to represent which is utterly ridiculous. Considering a transfusion will likely save a life, yet a life is supposed to be sacrificed for the sake of that which represents it.