The idea is simple. I think we ordinary learn with past experiences trying to understand in an incremental way. What if the brain also can take advantage of a future step in this process of learning. If we know where the knowledge is going next then maybe the brain can take advantage of this and organize in a simpler manner. So the idea is that we teach the present step and just a little bit of the future step during the same time period. Because the future step has been presented a little the guess is that this step will be learned a little faster and more connected than with the ordinary incremental way. An example would be teaching about derivation and during the same time period present a little about integration.
I think this shows how you can create different learning paths and not just the forward incremental way.