Here is what I got out of the letters:
1. Putting blood in your body is bad.
2. Putting blood fractions in your body is up to your conscience.
3. If you don't understand this, don't worry about it ("it would be appropriate at this time to let the matter rest" - August 24, 1998)
4. If you do something wrong, you will be disfellowshipped.
They have setup cryptic rules that they themselves do not understand, yet if you break one of the rules, they will destroy your life.