Is Dallas Keuchel the cat or the mouse?

One of the weird, dumb things about people is our endless willingness to believe in easy cause-and-effect relationships. Coffee causes cancer. Cell phone waves fry your brain. Coffee prevents cancer. The home run derby causes slumps.

Spitting on low Dallas Keuchel two-seamers spelled doom in 2015. Spitting on low Dallas Keuchel two-seamers was the path to salvation in 2016.

Cause-and-effect relationships are actually supremely complicated, daunting to untangle and near impossible to be sure about (not that it stops our multiple-choice-test-educated brains from feeling sure, anyway).

So when I describe how 2015 AL Cy Young winner fell upon hard times in 2016, as my colleague Joe Clarkin ably did earlier this offseason, realize that he is simply the latest case in our perennially flawed endeavor to separate that dynamic duo of deception. Perhaps, he can be the one that cures us of our overconfidence.

Probably not, though.

Keuchel’s 2015 strategy seemed maniacally simple. As the functional strike zone invaded the territory south of the hollow of the kneecap, he threw grounder-inducing pitches in the borderline areas where swings were basically punch-free and non-swings were somewhat likely to result in called strikes.

He complemented the headlining two-seamer with a slider that started in the same areas as the two-seamers and then dove from the land of little hope to the land of none.

FanGraphs’ rolling averages for his zone rate and opposing hitters’ chase rates show that they began 2015 holding off pretty well. But as Keuchel upped his slider usage and accumulated called strikes, hitters began chasing more and more – believing, perhaps, that they were being tricked into staring at borderline two-seamers. As they chased more and more, he sent pitches flying farther and farther outside the zone.

Over the second half of the 2015 regular season, Keuchel threw just 36.3 percent of his pitches in the zone, and reaped the benefits of even more ill-advised swings.

Like a cat and a mouse circling a recliner until the mouse winds up chasing the cat, this head-spinning process somehow reversed itself in 2016. Hitters stopped chasing, and Keuchel soon reacted by throwing in the zone far more often. His two-seamer, in particular, wound up in the zone 50.8 percent of the time in 2016 after arriving there just 44.1 percent of the time in 2015. Hitters forced him back toward the plate.

Charts via Brooks Baseball

It didn’t help the Astros ace that the strike zone ceased to sag to mid-shin level, and it should be noted that his velocity dropped a tick in a season shortened by injury.

The thing that remained constant throughout all of this: Anyone can make contact on anything Keuchel throws in the zone. That’s not to say it will be good contact, but it will be contact, an opportunity for things to go wrong. Contact on pitches in the zone is especially likely to end poorly for pitchers. And it did. As hitters stared him back toward the center of the zone, plate appearances ending on Keuchel’s two-seamer were resulting in a .315/.366/.476 slash line.

Earlier this winter, I concocted a way of visualizing how pitchers go about their task, based on league averages for zone rate and zone-contact rate. Basically: How often do pitchers feel comfortable coming into the zone? And are they missing bats when they do so? Dubbing it the Pitcher Approach Matrix, I used it to express some confidence that Danny Duffy’s breakout was legitimate. Duffy falls in the extreme reaches of the matrix colonized by pitchers who can get whiffs with strikes, a la Max Scherzer and Clayton Kershaw.

To the great disappointment of the parts of our brains that just want “the answer,” it doesn’t tell us anything about who is good, or how to be good, because there are lots of ways to do that. You’ll find excellent pitchers all over the matrix. What I believe the matrix can help with is assessing volatility.

If Scherzer or Kershaw can carry on throwing their pitches with similar movement and velocity (no small feat, but you get the idea), any great changes in performance would have to originate from a fairly small list of suspects. Bad luck, worsened command or a change in the home run environment of the league or their home park might come up. Even there, it’s not totally clear that worsened command would have too much of an effect on these guys, who can collect swinging strikes without much worry over location.

The pure ability of the hurlers in the upper right corner is enviable. Every pitcher would throw bat-missing stuff in the zone if they could.

Most just can’t. So they build more complex plans of attack – like Keuchel’s barrage of borderline worm-missiles – in response to their limitations. Some boast arsenals that are difficult to hit, but most effective outside the zone – the Chris Archers and Francisco Lirianos of the world. Others peer into the mitt confident they can place their pitches not only in the zone, but in the areas that will allow them to capitalize on the contact they aren’t adept at avoiding – Jose Quintana and Bartolo Colon come to mind.

Some, like Keuchel, attempt to lure hitters outside the zone to counteract their bat-missing deficiency. The tactic can work like gangbusters, but it also introduces a larger load of variables into the pitcher’s equation for success.

The strike zone Keuchel manipulated in 2015 changed slightly in 2016. Had he thrown precisely the same pitches, in the same order, to the same batters in 2016, it almost certainly would have turned out worse just because of the less expansive nature of the bottom of the zone.

And, of course, he also ran headlong into hitters who had come up with a plan to beat him. With a painful season of mass failure under their belts, they learned what to look for, and they began to tee off on Keuchel’s bread and butter.

The general approach also fits breakout Cubs starter Kyle Hendricks, as well as latter-day Felix Hernandez and Zack Greinke. They have different methods of accomplishing the task – methods that seem harder to adjust to than Keuchel’s, one might argue – but they remain vulnerable to a variety of landmines all the same, from downgrades in the pitch-framing department to the same sort of widespread hitter adjustments that, in part, felled Keuchel’s 2016.

Whether Keuchel or Hendricks or any of these chase-dependent pitchers emerge from 2017 looking like cats or like mice is anyone’s guess. The approach they share doesn’t preclude them from repeating success, but it makes it that success difficult to accurately envision. Chris Sale might tweak his approach a bit, as he did last year, but being able to throw strikes that also serve as swing-and-miss offerings can cure many ills.

These pitchers have told us through performance that they don’t believe they can afford to be less fine, or more predictable. Thus, their future incarnations are likely to look more different than the future versions of their strike-throwing and/or bat-missing contemporaries.

It’s not necessarily bad, but it presents more doors where they walk into 4.50 ERAs or huge walk rates or massive home run problems.

That, however, is about as much as we can say for our understanding of this cause-and-effect cycle. The hitters will notice whatever they do – throwing the slider more often seemed to be Keuchel’s late-2016 idea – and eventually force more evolution. Believing in their ability to adapt is a choice you, and their clubs, can make. Believing in the sustainability of their past results is probably going to leave you dazed and confused.