So Mr. Echo / Locke have a vision that leads them to the main hatch where they discover a new video tape that gives them information about something that is supposed to be important to the Darma chaps but in the end means NOTHING because the hatch has a fricken fail-safe key. So the vision validates the presence of hyper-spirituality but the vision only served to prolong the episode so that the finale could end on episode 24.
Again, it’s not about the story, it’s only about the yarn.