There is no auto-target in Skyrim. There is a "slight magnetism," which is very different. An obvious example of the slight magnetism was when the Dragonborn turns and slashes the dragon on it's side while it was flying by. It's only meant to make combat more engaging and intense, but not meant to take away or cripple the player experience. A lot of FPS games have a magnetism to a degree just to keep things fun and competitive.