I am trying to simulate paper folding using cluster deformer. It is a simple setup.
At first I applied a diagonal fold to my mesh with less than 180 degree to avoid overlapping and then delete history. From this setup, I applied a cluster deformer to the single top vertex (Fig. A) and then rotated it along a locator point (Fig. B). I use double-sided shader by utilizing the normals (Fig. C).

Fig. D shows the initial state before applying a mountain-fold to it. Then I applied a rotation and it looks fine up to 89 degrees (Fig E).