Although I'm on the author's side, things like http://www.independent.co.uk/news/uk/home-news/alzheimers-tr... make me think twice on whether I'm right or wrong.
2. In many cases, new treatments don't help outside of the early stages — in the story you linked, the description suggests that the treatment wouldn't help someone who's already in an advanced stage of the disease. Great for the future, perhaps, but cold comfort to when someone is already past the point of permanent damage.