I've actually had this exact problem with Instagram.

  1. My teenage daughter shows me picture of a girl she knows but doesn't like.
  2. I don't have my glasses so I double-tap to try to zoom in a bit.
  3. My daughter screams that the girl now knows that she was looking at her picture.
  4. I quickly double-tap again to un-like the photo.
  5. My daughter glares at me because she knows that the damage is already done.

In fact, I can relate to the guy in the original story. Fortunately, I only earned my daughters short lived wrath and didn't lose my job.