Derek Thompson surveys the scientific literature of the strike zone today to demonstrate that fewer homers hit is bad for baseball, and that fewer homers are being hit today for two primary reasons:
1) Starting in 2006 stringent drug testing reduced the use of PEDs in the game.
2) Starting in 2006, the introduction of the pitchFX system increased the size of the strike zone, most notably by expanding the low part downward. Follow the link for more about pitchFX, a video and computer sensor system that tracks the speed and trajectory of every major league pitch.
It’s an interesting piece, especially the chart that shows how much better the umpires have gotten since their work could be not only reviewed, but reviewed against real objective data (not that it is always perfect).
As someone who, perhaps naively, argued in the early days of the homer boom that it looked to me like the real cause was a flattening strike zone, which meant hitters could look inside or outside and not so much up and down, the data strongly suggests this is at least partially true. One researcher says that the decline in homers since 2006 is 40 percent due to changes in the strike zone.
That’s a lot, and could be true, but I suspect we haven’t heard the last of this.
At the end of his piece Thompson lists other causes for a drop in offensive power, including defense (though this shouldn’t have much of an impact on homer rates) and changes in the baseball, but when he tries to remind us all of the shadow of PEDs use on this issue, he falters.
He writes:
Perhaps most importantly, the harsh 2006 rules against performance-enhancing drugs offer a compelling explanation for baseball’s dearth of power—although it’s odd that baseball’s minor leagues haven’t seen a similar decline in offensive performance since their own steroid policy was implemented.
The minor league drug policy is in many ways more stringent than the major league program. What the minor leagues don’t have is pitchFX and the absolutely best umpires.
Oh, and to answer the question in the headline: pitchFX didn’t destroy baseball, it simply made the administration of the game more accurate and fair.
But if the low run environment proves to be persistent and unpopular, MLB can raise the bottom of the strike zone back to 2006 levels. That’s what they do. (It perhaps pertains that it was part of my argument about the power of the strike zone to change other outcomes, that umpires would be inclined to make this adjustment in an ad hoc way if the pitchers became too dominant, in order to help sustain the game’s equilibrium, which wavers but never cracks.)
