And that's fine - there are some things in life that aren't subject to spread-sheet micro-analyses.
AA saved my life - maybe I would have got sober another way, but that doesn't matter, this is the way I did it - I'm living in today, can't worry about "what if's".
I'm clean and sober today, and that's what matters. From a run-away freight train plowing through anything and anyone in my path - to a usefull member of society. And a sane, Conservative one at that.
Praise God! (And no, I'm not being sarcastic.)
My point is that although some individuals attribute their sobriety to AA, there is no way of knowing if it is an effective program or not. It might actually hurt more people than it helps. We just don't know, and we cannot know.