I told my wife that I wanted to donate blood, in case a JW needs a blood fraction, they can take it out of my blood...
i mentioned this point to an elder and he thought about it for a minute and then agreed with me. So many dont even think about the double-standard here.
as for tearing up your card - congrats. I shredded my in an actual paper shredder a few months ago. Lately with all the talks about filling out the blood cards I am hoping my wife doesnt ask about it!