This debate over whether the blood is stored for a little while or maintained in a continuous circuit shows the legalistic approach and the rule binding approach to the "blood issue" these days. I cannot help but think of the Watchtower's own words in condemnation of the Pharisees, who had a similar approach to doctrine in Jesus' day.
w029/1p.11par.14"NeverHasAnotherManSpokenLikeThis"***
"On another occasion, Jesus denounced the Pharisees as "blind guides, who strain out the gnat but gulp down the camel." (Matthew 23:24) This was a particularly powerful use of hyperbole. Why? The contrast between a tiny gnat and a camel, which was one of the largest animals known to Jesus’ hearers, was striking. It is estimated that it would take up to 70 million gnats to equal the weight of an average camel! Also, Jesus knew that the Pharisees strained their wine through a cloth sieve. Those sticklers for rules did that in order to avoid swallowing a gnat and thereby become ceremonially unclean. Yet, they figuratively gulped down the camel, which was also unclean. (Leviticus 11:4, 21-24) Jesus’ point was clear. The Pharisees meticulously complied with the smallest of the Law’s requirements, but they disregarded the weightier matters—"justice and mercy and faithfulness." (Matthew 23:23) How clearly Jesus exposed them for what they were"
If the cap fits... wear it...