I looked at the first one (and played that part today actually) and you can only see it if you play it frame by frame. Plus, since it's the cut scene it's not actually the game model. The game model is static.
The batarang wings are 1/8" thick and the center part is 3/16" thick. That and the size of the of the wings themselves make it impossible to have the wings mobile without drastically altering the structure of the batarang itself, which is what happens on that instructables site tutorial. The center piece is thicker and a 4th piece is added below to make it mobile. Going frame by frame shows the two wings pointing downward which isn't actually possible (i don't think) with the actual game model. The point at which the wings would actually touch would be when they've rotated downward about 50-60 degrees, the cutscene has them pointing 90 degrees down.
There are 2 pic's of the game model attached. The game model, FWIW, is one single object. It's not in separate pieces so it can't move.
The first is if you rotate the wings about the center 30 degrees - that's the point at which the two wings would touch. The second is how it's shown, more ore less, iin the cutscene. The wings are rotated down about 80 degrees, but they have to physically move off the center. The center point of the wings is straight up from the center of the wings about an inch in empty space. They have to detach from the center to get into that position.
They only way I can see to fold them is to more than double the size of the center cylinder and a mechanism has to be created that when folded, the wings would double up on one another and when pulled apart, one wing snaps down to the folded out position. To do so, you probably have to increase the center cylinder to about 3/8-1/4" if not more. By design, it's 3/16".
