Direction Dupe is a glitch that makes the game think you are going down a certain direction but you actually go down the other one.
This occurs when you change the direction of a juction on the last available frame.
In this video, I did it on the last junction so I went left (the correct way) but the game though I went right (the wrong way) so it makes me go back to the forest entrance. If you do it on a junction in this forest, the direction trees won't load up anymore but you can still make your way to the exit (if you're lucky). This glitch have currently no uses.