It probably won't. But he KNOWS the other stuff didn't work.
Personally I don't think it WILL work. I think she is incorrigible. I don't think anything will bring her around. But this method clears out the talktalktalk and the underbrush. The clears the landscape. Then she and hd can see what they're really dealing with.
And he IS changing himself, by speaking up, for one thing.
Who knows? It may work.
This method is not designed to change her; it's designed to clarify the situation.