If anyone else is looking for this solution: editing the .js files does not do anything. At all. What you can do, is disable the animation altogether. Navigate to your agile/js/libs folder, open jquery.flexslider.js and scroll all the way down to the //Flexslider: Default Settings. Change ‘slideshow: true,’ to ‘slideshow: false,’. Done.
In my opinion, this is better than the fast sliding defaults. This way, visitors can slide when they want to, but don’t have to. And they won’t be distracted by constantly switching images, which is annoying in Blog posts.