Blood was the first brick that fell for me. I tried to defend it (I will spare my attempt at apologetics, but it was along the Firpo Carr route, and kind of what i hear from people when I have the discussion with them now namely.....that its bad medicine).
My favorite arguments against the insanity that is the blood doctrine are as follows.
1) White blood cells are forbidden, but Albumin is "christian to decide". Albumin however is more present in blood than WBC's by double. As far as i can tell there is no real medical designation for "main components" in a real sense. There are 3 sections that separate when put through a centrifuge, but that is fractional, just in the way that if they take it further, they are further fractioning blood. the WT explanation for this is like a pie. Apples, sugar coat, crust......main components. But could flour, water (from the apple), sugar....be called a pie? So the criteria for what makes something too much like blood to be blood is important.......but as far as I can see there is no criteria.
2) The bible says to abstain from blood. it does. But what does this mean (if you follow the bible as an authoritative source). Well......Jesus broke the sabbath, and set a model for putting people above laws. Did he do this just to enforce more laws in the end, especially something so gnat straining as the blood doctrine? Paul can explain it. In the same scripture that says to abstain from blood, they are also told to not eat meat sacrificed to idols. But later in 1 Cor 10:25 Paul says this when the meat in the meat markets source can't really be verified.
“So you may eat any meat
that is sold in the marketplace without raising questions of conscience.”
So this could not have been universal abstention. It was a reasonable conclusion to a complicated issue at the time, because the Jews were used to the letter of the law, and their mentality had to become a little more at ease in order to follow Jesus. Jesus made people and life a concern OVER the law. End of story. Numerous examples abound. Even in the mosaic law there was an arrangement AFTER the Noachian creed was spoken, for Isrealites to eat the flesh of an animal not properly bled (but they would remain unclean for 1 day). Maybe if you take blood, WT would disfellowship you for one day? Ha! My point is of course that it isn't biblical even in a vague sense, except when you haven't taken any time to research alternative views, and take the scripture out of the context of the book it is written in.
3) The argument FOR JW's stance from their perspective seems to not linger on doctrine. They really won't engage the lack of logic, and they will not discuss it from the scriptures standpoint. Its like they just point to Acts and say....see? No their apologetics revolve around whether blood is good medicine or not. If there is something better for us, and we do better without receiving it (due to modern medicine advancements), then they must have been right all of this time! In fact, you should be grateful because witnesses have driven this change and helped the world discover the dangers of blood. Can you imagine the arrogance of that view. Coupled with that, a CO who is (was) a family friend told me very directly that in 2008 they stopped disfellowshipping for it, and just try to readjust the person. If this is the case, why would they not communicate it to the flock? Why was it only some high level speak to the CO's thing? Probably pressure from the outside world to abandon this archaic was of thinking? In closing his point was that since taking on the doctrine, there is evidence of growth and "Jehovah has not transferred the responsibility of the preaching work to some other more favored organization". Needless to say we didn't go beyond that point.
In short, transfusing isn't eating, and eating isn't transfusing. Because the context of scripture is of course eating only with regard to the abstention protocols, one could easily argue that a transfusion far from being a misuse of blood, is using it exactly what for what it is INTENDED to do. That along should make it a conscience matter across the board.
They have elevated the symbol of life above life itself.
It took me a while, but these things are what finally freed my mind. i discovered it while serving in a remote congregation in a far away country. That was a weird year.