User blog:DJ TechnoBrat/moving from one cover spot to another in a gunfight

Early in the game when I was attacking some guy's house with the Sherriff, there was a tutorial on moving from one cover spot to another one (like from behind a rock to behind a box). I can't seem to find anything about how to do that, nor can I reproduce it.

Did they just teach us the "jump over cover" button, and I thought that there was something more like the Gears Of War style "duck-run from one cover to another"? I.e., is this really simple and I'm looking for something more complicated?