When using the Elytra, you can see the player's camera going down a little bit as you fall down.
It isn't a smooth movement. As you fall from something like 2 blocks high, your camera suddenly moves down.
As you can see on the screenshot, my camera is down a bit and it looks like I'm in the ground. When I land, the camera goes up to normal.

The screenshot is taken on a world where I only used 15w42a.