Blog post author here, yes you are correct, I falsely assumed that I can only insert and manipulate one liners in the file due to these commands being the first things I learned about how to use pass, so I just moved away quickly without looking deeper.
As many have pointed out, one big flaw in this blog post is that pass allows multi-line edit, I've corrected that in the blog post.
Many alternatives have been suggested here, I will sure to try them out someday, thanks!