I don't recall the exact details, but there was
once an editor called "em"
(Editor for Mortals). I remember thinking: what sort of an idiot would
call it that, with the "e" and "r" keys adjacent to each
other? I wonder how many files were lost that way...
you can download, build and
use em making immediately clear that em was much easier
to use than ed. Nevertheless em was only (another) step in between ed and vi.
http://pgas.freeshell.org/C/em/
http://www.tuhs.org/Archive/Applications/Em_Editor/
http://www.coulouris.net/cs_history/em_story/emsource/