Folded surfaces are segmented and new curves created where the surface is folded at an angle greater than the specified Max angle. It will help the surface Mesher (Shell) as additional curves are placed on the surface. The Max angle option measures from each end of the surface. The first point, from one edge, whose tangent deviates more than specified angle (default is 90 degrees) splits the surface. For a cylinder, this will generate more than one curve.