The second sentence makes the first sentence literally impossible though. You can't impede/hinder a runner if the runner isn't close enough to be impeded. A third baseman can be standing directly next to third base, and she's not actually impeding the batter-runner if that player stops at first base. But once that batter-runner rounds second and starts going to third, well, now we may have obstruction.
So I don't see how the runner's distance from the base can be irrelevant. If a catcher is "blocking the plate" when the runner hits third base, but she moves out of the way when the runner is halfway home, that's not obstruction. So obviously the runner's distance from the base (or distance from the potentially obstructing fielder) does matter.
