When the Detroit Tigers traded Doug Fister to the Washington Nationals back in December for a a middling left-handed pitching prospect and some change, it was, well, baffling. Here we are a few months later, and it’s no longer baffling. Yes, it’s self-destructive. It’s ruinous. It’s loony. It might be the trade that changed the entire face of baseball for 2014. Baffling just isn’t nearly a big enough word now.

Let’s do a quick review:

Washington

Last year: The Nationals were sixth in the National League in runs allowed, gave a struggling Dan Haren 30 starts and finished second in the National League East and out of the playoffs.

This year: The Nationals lead the NL in ERA (more than a half run lower than last year), they are six games up in the in the National League East, and Fister is their best pitcher.

Detroit

Last year: The Tigers were third in the American League in ERA, Fister made 32 starts for them (the Tigers went 18-14 in those starts), and the team won 93 games, won the American League Central and reached the ALCS.

This year: The Tigers are 10th in the league in ERA, Fister’s starts were mostly taken up by since-traded Drew Smyly (team went 6-12 in his starts) and the player acquired in the deal, Robbie Ray (1-4 in his starts). Detroit finds itself one and a half games behind the Kansas City Royals.

It was a disastrous deal for Detroit, and it was a probably a season-saving one for Washington, and it leads to the question that made little sense at the time and makes no sense at all now: Why in the heck did Tigers GM Dave Dombrowski do it?

There were explanations at the time. One of those explanations was that the Tigers were trying to open up a spot in the rotation for Smyly, a talented lefty who had pitched very well in relief in 2013. The Tigers talked on and on about how important it was to get Smyly into the rotation — they were supposedly worried that if they gave him another year in the pen, he might never make the transition to starter.

OK. What else? Well, Dombrowski made a point of saying how much he and his staff liked Robbie Ray, the pitching prospect they got in return. On this front, Mike Rizzo concurred — just a couple of weeks ago, when I talked to Rizzo about how good Fister has been, Rizzo quickly said: “Well, we gave up a lot to get him.”

What else? OK, there’s the money. The Tigers have a huge payroll, but even the big payroll teams would like to save money where they can. With Fister entering his later arbitration years (he signed for $7.2 million this year) and Smyly apparently ready to start, Fister was perhaps expensive enough to move.

Now, with a a few months of clarity added to the picture, none of these things makes sense.

1. Smyly? No. The Tigers have already traded away Smyly to get David Price and make a desperate run for the playoffs with a wounded and uneven team.

2. An under-appreciation of Ray? Too early to tell but early signs say: No. Ray has struggled in his early starts which doesn’t mean much, but I still haven’t talked to a scout who loves him.

3. Money? No. When Dombrowski realized that his team was short on pitching, he went out and got David Price who is making twice as much as Fister and will make more next year.

So … why?

Nobody is saying why, but I have a guess. It’s a guess that directly relates to something I see all around baseball, even at some of the more enlightened places. I have invented a word for it: Fistrust.

FISTRUST (pronounced FIS-truh-st, noun): A deep suspicion and profound lack of confidence in pitchers who cannot throw 90 mph.

The radar gun has changed baseball in so many ways. It has changed the way scouts rate players. It has changed the way pitchers train. It has changed modern bullpens and changed the types of pitches that batters will see in the eighth and ninth innings. It has changed the way people watch the game too — how often do you find yourself at a ballpark or on television, and a pitcher throws a fastball by a hitter, and you think: “How fast was that?” And you’re actually peeved if that information is not immediately available.

One of the ways I think it has changed the game is that the radar gun has sparked a powerful (and often involuntary) mistrust — fistrust — of pitchers who are getting people out when their fastballs top out in the 80s. I see it all over the game — even among some of the smartest and most forward-thinking people in baseball. I had one of the game’s truly great minds tell me, “I KNOW I shouldn’t worry about the radar gun, but dammit, I see a guy getting people out at 87 miles per hour, and I can’t help it.”

Right. They just can’t help it. So much of pitching is a mystery. Nobody REALLY knows how many pitches or innings or days between starts is the right number. The scouting and development of pitchers is so hit and miss. The radar gun is something tangible in that sea of confusion, and so when the reading says 87 mph, the mind simply has a hard time associating that with pitching success.

Doug Fister was a seventh-round pick as a senior at Fresno State — “seventh-round pick” and “drafted as a senior” almost always add up to “non-prospect.” Though he stood 6-foot-8, he never did throw very hard — his calling card was impeccable control and a heavy sinking fastball that (in theory) batters would top into the ground.

He meandered for a while with Seattle, pitching way better than his won-loss record (well, his won-loss record was 12-30, so ANYTHING would be better than that) and then he came to Detroit in what seemed a minor deal in 2011 and basically pitched the Tigers to their first division title in almost a quarter century. On August 20, the Tigers were nine games over .500 and leading a lethargic division. The Tigers won Fister’s next seven starts — he allowed one earned run or less in every one of them. Detroit ended up winning the division by 15 games.

Did the Tigers believe? Maybe. Maybe not. Fister did strike out nine Kansas City Royals in a row in 2012 — that’s an American League record — but in general the strikeout wasn’t a big part of his game. His fastball didn’t hit 90, and his success seemed to rely on shaky things like keeping the ball in the ballpark and not walking hitters. I once had a baseball general manager tell me that the one thing a pitcher never wants to be called is a “sinker-slider type pitcher.” The GM explained: “That means he can’t throw hard enough, and doesn’t have an out pitch.” Fister was the very definition of a sinker-slider type pitcher.

He also was very good — good ERA, good Fielding Independent Pitching numbers, good results. He gave up hits, and he didn’t intimidate anybody even at 6-foot-8, but the guy gave you quality starts time and again and for all the griping about quality starts, teams tend to win a high percentage of them.

This leads to my guess: I just don’t think the Tigers trusted Fister coming into the season. They have a pitching staff loaded with dazzling stuff and, against that canvas, Fister’s sinkers and sliders just seemed uninteresting to them. This wasn’t only true for the Tigers, by the way. I don’t think many teams around baseball appreciated Fister. I mean Dombrowski’s a smart guy — you know he shopped Fister around, and it seems the Nationals’ uninspiring offer was the best one made.

Think about that for a minute. You would think that teams would be breaking down doors to get at a pitcher with Doug Fister’s production the last three years. I mean, sheesh the Twins gave Ricky Nolasco $50 million, and the Brewers gave Matt Garza $50 million, and the Orioles gave Ubaldo Jiminez $50 million and the Phillies gave A.J. Burnett $16 million for one year,

But Nolasco, Garza, Jiminez, Burnett, they all throw 90-plus. Doug Fister doesn’t.

Fister is pitching much better than any of those others, something that should not have been that hard to predict. The guy can pitch. Right now he’s pitching about as well as anybody East of Kings Felix and Kershaw. With Stephen Strasburg having a weird year and Gio Gonzalez having a down year, Fister has been at the heart of a Nationals team that is a real World Series threat.

Meanwhile, the Tigers pitching staff is a mess — Anibal Sanchez is hurt, Justin Verlander can’t get anyone out, Max Scherzer is a a few weeks away from becoming baseball’s most sought-after free agent pitcher. They sure could use a solid sinker-slider pitcher who doesn’t walk anybody and has a 1.89 ERA since the middle of May. Then again, who couldn’t use that guy?