I didn't read a lot of this thread because I typically don't like how drug threads go on here, but as to the point about getting addicted so you can "bravely kick" - I really doubt that's a popular line of thinking. I think it's probably that so many people (including myself) think "well it's not going to happen to me" and then it does.
As for defending heroin, or drugs in general, I just wanna say that they prevented me from killing myself for a number of years. It was a tool for me to numb my mind and quiet my painful feelings. After a while, they didn't help anymore. The drugs work until they don't.
And I'm a little hippie woo woo, but I don't think heroin or alcohol on their own have an evil to it, an intention, a vibe, or whatever to them.