This technique is called "stacked focus" and was originally created to produce microscopic pictures.
I did some, using a very painful software application, that takes forever to produce the results.
I didn't knew that this facility is now available inside the camera.
Thank you for bring our attention to this. It should be a great tool for static macro pics.
As you mentioned, the pain is that the object must be 100% static.
Cheers,
Nilo