bug#26525: `sit-for' in Flyspell slows typing down, hogs 90% of CPU

[Clément Pit-Claudel]

The relevant piece of code seems to be this:

      (cond
       ((get this-command 'flyspell-deplacement)
        (not (eq flyspell-previous-command this-command)))
       ((get this-command 'flyspell-delayed)
        ;; The current command is not delayed, that
        ;; is that we must check the word now.
        (and (not unread-command-events)
             (sit-for flyspell-delay)))
       (t t)))

But the condition and the comment seem at odds, and it doesn't say much about 
why it calls `sit-for`.

Clément.