Tomi Ollila <tomi.ollila@iki.fi> writes:

> ... but I think I am not biased when I think that if ctrl-x ctrl-s
> does something more magical than simple (save-buffer) in buffers that
> looks like text editing buffer, that is going to be unexpected disturbing
> functionality to someone (else like me)...

This is a valid point. On the other hand the binding is copied from
Gnus, which also includes at least _some_ magic

      http://www.gnu.org/software/emacs/manual/html_node/gnus/Drafts.html

Of course we don't need to slavishly follow Gnus (that way lies
madness), but there is also a group of users familiar with its draft
handling.