Posted on subreddit. Still a small fraction of all users, though.

https://www.reddit.com/r/emacs/comments/2x13db/does_anyone_ever_use_saveexcursion_to_preserve/
On Feb 24, 2015 5:11 PM, "Barry Warsaw" <barry@python.org> wrote:

> On Feb 24, 2015, at 02:27 PM, Stefan Monnier wrote:
>
> >It does seem risky.  At the same time, I can't find a single piece of code
> >that relies on this functionality so far.  So either the risk is
> minuscule,
> >or I haven't looked in the right way.  Hence this thread, to try and see
> who
> >and how might rely on this.
>
> Sure, and that's appreciated, but of course most Emacs users probably don't
> read this mailing list.  :)
>
> Cheers,
> -Barry
>