No. It's a custom title and a in-reference to Douglas Adam's works of science fiction.
In DA's story, there is a huge Wikipedia-like digital encyclopedia with anything and everything listed in it.
The aliens didn't know a thing about Earth, so they sent a researcher/author to Earth to do some research. He wrote a book-long entry, sent it back to the editor, who then told him that it was too long and there were more important planets out there to spend this room on. The entry was shortened to one word: "Harmless."
After the researcher complained that it was an un-fair summation of matters on this planet, they revised the entry to read: "Mostly Harmless."
There are many references to Science Fiction on NeoSmart Technologies, if you know where to look