Is that not this part?
> > but if my computer keeps guessing them, it can know when it is right. And my computer guesses really, really fast.
> > but if my computer keeps guessing them, it can know when it is right. And my computer guesses really, really fast.
And as far as operational security is concerned, this fixates on just that one threat that the author talks about at the end, which depends on weak password.