And that destroys any argument that the Prohibition is about Transfusions. Thanks TD, couldn't be more concise.
From what I've seen in JW literature, this is not unusual (i.e. A facile treatment of a subject in one publication is undermined by a more thorough treatment in another.)
The JW Bible Encyclopedia, Insight On The Scriptures Vol II page 587 states with regard to the Decree:
"The decision then made was that circumcision was not required for Gentile believers but that they should keep free from idolatry, from eating and drinking of blood and from sexual immorality."
So clearly they do understand that the phrase, "Keep abstaining...from blood" was specific to its context
There is a view common among Bible scholars that the Decree was simply a temporary measure to ease the tension between Jewish and Gentile Christians. The wording is actually pretty weak. In both English and Ancient Greek the connotation is clearly one of voluntary compliance.
The JW parent organization argues against this viewpoint by (You guessed it) linking it back to earlier commands and/or appealing to scholars who do:
For example the October 22, 1990 issue of Awake! said on page 15:
“But those who respect the Creator's wishes do not treat it that way. 'You must not eat blood' was God's command to Noah and his descendants—all mankind. (Genesis 9:4) Eight centuries later He put that command in his Law to the Israelites. Fifteen centuries later he reaffirmed it once again to the Christian congregation: 'Abstain from blood.'—Acts 15:20.”
The June 15, 1991 Watchtower said on page 9:
“The early Christians upheld that divine prohibition. Commenting thereon, British scholar Joseph Benson said: "This prohibition of eating blood, given to Noah and all his posterity, and repeated to the Israelites . . . has never been revoked, but, on the contrary, has been confirmed under the New Testament, Acts xv.; and thereby made of perpetual obligation."
The June 15, 1978 issue of The Watchtower said on page 23:
“In "Origin and Beginnings of Christianity," Professor Eduard Meyer commented that the meaning of "blood" in Acts 15:29 was "the partaking of blood that was forbidden through the law (Gen. 9:4) imposed on Noah and so also on mankind as a whole."
So again, it is clear from both their direct statements and the authoritative sources they have chosen to appeal to that the JW's do understand that the mention of blood in the Decree was a reiteration of existing commands against eating it.
If we want to go back even farther, blood fractions were originally allowed on the basis that they did not qualify as "food."
"Each time the prohibition of blood is mentioned in the Scriptures it is in connection with taking it as food, and so it is as a nutrient that we are concerned with in its being forbidden...