Here's my best response to your objection, flamegrilled:
I strongly believe that everything can be placed into a bell curve: intelligence, height, how fast you can run, how long you'll live, etc...
And I think that survival levels with blood or without blood can also be placed in a bell curve.
Only one human in recorded history has lived past 120. The life expectancy is 85. Similarly, only a few humans can run 100 meters in less than 10 seconds, most run it in 20 seconds, only a few humans are above 2.50m in height, average is 1.80m, etc...
Only a few humans can survive, without harm, the levels of hemoglobin that some JW's have survived, such as 2.0 g/dl. The lowest accepted "safe" threshold is currently 7.0g/dl. JW's proved that the threshold of 10 was too high, and that it was acceptably safe to bring it to 7.0
But there are hundreds of other factors and I am not a doctor and I could be completely wrong here.
The many reports in the media show that you CAN attribute at least a higher, sometimes MUCH higher probability of death without blood, and you can MOST CERTAINLY argue that to transfuse is better than not to in cases of severe, acute blood loss (such as a car accident), or cases of severe anemia.
I read in some of the reports that doctors estimated XX% probability of survival with blood, and X% without. In one case it was 90% vs 5%. So it would be tough to argue that the refusal of blood was THE cause of death, the cause of death was the previous condition, but it can be argued that the lack of blood precipitated the death.
