bug#7273: 24.0.50; finally found what has been subtly corrupting my files over the years: C-. flyspell-auto-correct-word

[Chong Yidong]

jidanni@jidanni.org writes:

>>> P.S., what is the best way to disable C-.? global-(un)set-key?
>
> CY> should do the trick, once Flyspell is loaded.
>
> You will have to tell me what to put into .emacs.

Try this ---

(eval-after-load 'flyspell
  '(define-key flyspell-mode-map [(control ?\.)] nil))