the point of markdown is to `write` almost like plaintext to then be interpreted and re-rendered as proper html, not to be "readable" in plaintext, it is to be readable when you write it. it is not an improvement to plaintext and shouldn't be used to replace or enhance it. it's a poor man's html and belongs in it's own kind where the correct parser is to be used. plaintext is just that plain text, no special parser required.