So why are they not using this tech for balls/strikes? The point of this article is that during extra innings, umps are miscalling pitches. With Hawk-eye the ho

So why are they not using this tech for balls/strikes? The point of this article is that during extra innings, umps are miscalling pitches. With Hawk-eye the home base ump could know near-instantly if the ball is in the zone. Then there is just the arguments of the batter swinging..