I was thinking about the conversation between Jacob and Nemesis. He tells Jacob no matter what it always ends the same. Jacob says it only ends once and anything in between is progress.
What if Jacob was trying to change things the same way Dharma was trying to alter the valenzetti equation to avoid the end of the world.
If Jack's plan does work and the future has been changed, how long do you think it will be before everything is put back the way it was...through course correction