If you're wondering why the game seems to stutter so much while you run, it's likely because of the imposed camera shake associated with the run mode by the developers. It's actually really easy to turn off and improves the experience greatly. Here's how you do it:

1. In Steam click on The Witcher 3 and click on "Browse Local Files" - this will open a folder to the Witcher 3 directory.
2. Browse through to the following destination: content\content0\scripts\game\player
3. Open the file "player.ws" using a text editor of some sort (I recommend Notepad++, but even WordPad should work just fine).
4. Do a Find (ctrl+F) on the word "shake". It should lead to the following section of code:


if( useSprintingCameraAnim )
{
animation.animation = 'camera_shake_loop_lvl1_1';
animation.priority = CAP_High;
animation.blendIn = 1.f;
animation.blendOut = 1.f;
animation.weight = 1.5f;
animation.speed = 1.0f;
animation.loop = true;
animation.additive = true;
animation.reset = true;
camera.PlayAnimation( animation );
}

To remove the camera shake from the game, all that you have to do is place two // in front of that final "camera.PlayAnimation(animation);" line. The two slashes is used in programming to designate that the following line of text is not code, but rather a comment, and as a result it will not be run as if it were code, thus it will keep that command from executing when you're sprinting. The correct code should then look like this:


if( useSprintingCameraAnim )
{
animation.animation = 'camera_shake_loop_lvl1_1';
animation.priority = CAP_High;
animation.blendIn = 1.f;
animation.blendOut = 1.f;
animation.weight = 1.5f;
animation.speed = 1.0f;
animation.loop = true;
animation.additive = true;
animation.reset = true;
//camera.PlayAnimation( animation );
}

Save it in place - it should still be "player.ws", now while running there will be no more camera shake. :-)

Happy running!