Inserting Documentation Quotes15 Jul 2014, by Artur Malabarba.
Hopefully I'm not the only one who obsessively tries to abide by the
high codes of good practice and writes descriptive documentation on
defcustom. If so, I can't be the only one who
has grown tired of typing ` then ' inside Emacs doc strings.
The m key feels natural to me here, because I also use C-c m in LaTeX for quoting math, but you might find some other key more intuitive.