"Ugh, I don't understand why this idiot is just camping in the left lane!" My wife, Danger Girl, was getting just a bit angry in the passenger seat. It was late in the evening, as Paul Simon used to say, and we were still more than two hundred miles away from Las Vegas, stuck behind a blue Toyota Camry with the requisite bumper-corner dent. "Why won't he just move over? What is his problem?" Behind us, a relatively new Ford Explorer lost patience with the proceedings, swung out into the right lane, and blasted by both of us at full throttle. I took a quick glance at the speedometer of our rented C-Class.
"You'll never believe this," I told my wife, "but we are doing 87 miles per hour right now." There was a pause, and then a response:
"So? Go around him anyway." Which I duly did, flogging the poor four-banger Benz past the 100 mark on the dial. As I eased up on the throttle, a white Sienna passed me in the right lane, honked, and made a deliberate Earnhardt-style chop across my front bumper. We were doing about 95 mph and we were damn near the slowest traffic on the road.
Two and a half hours later, I caught up with the Explorer and the Sienna just outside of the Las Vegas Strip, when the freeway widened out to six mostly-empty lanes in each direction. They were doing a placid 68 in a 65, clogging up the left lane like they had all the time in the world. What had changed? What possess someone to drive more than 100 miles per hour in a minivan or SUV, only to wind up blocking traffic a few hours later?
I've been a student of highway behavior for a long time, and I've read a lot of material on the subject from scholars of all kinds, but I've come to believe that the best summation available of irrational driving is . It's chock full of insights, but there are two in particular that I think apply to the Case Of The (Occasionally) Triple-Digit Minivan.
The first applies to all vehicles, not just Siennas, and it has to do with speed perception over time. Human beings are not designed to travel at high speed; as a result, we exhibit some truly irrational behavior once we exceed the airspeed velocity of an unladen swallow. One of our less-than-charming little quirks: we tend to overestimate speed as we are accelerating up to freeway pace. That's why people in front of you are always trying to merge onto the freeway at 48 mph: they think they're going pretty fast. Very few people accelerate up to a proper merging speed by default. We are almost all too slow. This is even true of club racers. I've caught myself doing a lazy merge more than once.
It gets worse. Once we're up to speed, we start to become accustomed to it, and we shift from overestimating our current velocity to underestimating it. The longer we drive, the slower we think we're going, until something happens to reset our perception.
So let's consider that long drive from Los Angeles to Las Vegas, on a single freeway that's mostly just two lanes in either direction. We start off by merging too slowly—and sure enough, everybody I saw getting on the road during my trip was an active impediment to the lane they were joining. As the hours drag on, we start to underestimate our speed. This is particularly true when there's nothing around—most of that drive is empty desert. So we go just a little bit faster every half hour or so.
Meanwhile, everybody around us is also gradually adding speed. So if you're the kind of person who feels the need to outpace traffic, you'll continue increasing your speed to beat them. Before you know it, you're doing 100 mph in a Ford Explorer. It would probably never occur to you to drive 100 mph on a short freeway commute to work. If you saw someone else doing it, you'd probably call them a maniac or an idiot. But after three hours of looking at the same empty desert vista, you become immune to the normal sensations of speed.
The solution to this is to set your cruise control and leave it alone, as I eventually did. But most people don't have that kind of discipline or patience. Their speed ebbs and flows with the cars around them. So by the time you get to Vegas, you're doing aggressive, dangerous speed.
But what happens once you get there? The freeway opens up. There are streetlights. You have a thousand colorful things to look at. It's a reset button for your perception of speed and travel. Poof! The 100 mph minivan is now the 68 mph minivan. Both speeds felt right at the time, but the first one can be deadly and the second is frustrating to fellow motorists.
Once we're aware of this phenomenon, we can account for it and try to mitigate the problems it causes. Don't get caught up in that LA-to-LV Cannonball Run. Set the cruise control and keep your temper off the boil. Unless, that is, you're one of those folks who rents a Lamborghini for the drive. In that case, you're probably going to open it up to see what it can do...
...and then you'll settle down to the point where you're going slower than the minivans. Why is that? It's due to a second accident of human evolution. We tend to take our speed cues from the motion of the ground beneath us. The farther away your eyes are from the ground, the slower you think you're going. A Dutch study showed that than they were in an identical car at passenger-car height. Two-thirds of the drivers didn't notice any difference; some of the ones who did notice thought they were actually going slower in the higher vehicle.
It's obvious to anyone with more than a decade's worth of experience on American roads that average freeway speeds have increased considerably over the past few years. I always put it down to the lower in-car noise levels and better handling capabilities of modern cars, traits that make drivers more secure in going faster—but it turns out that the ever-increasing seat height of everyday vehicles is also to blame.
There's a sad irony in the relationship between vehicle height and vehicle speed, because a raised center of gravity significantly decreases a vehicle's ability to safely handle a high-speed evasion or even a tire blowout. I know, I know, you keep reading about how the Such-And-Such Crossover is a "sports car on stilts." That's a snappy way to describe it, but trust me, the laws of physics are immune to marketing hype, and they continue to punish jacked-up cars and trucks when the proverbial spackling hits the proverbial fan.
Oh well. At least we solved the mystery of the 100-mph minivan. It's partly adaptation to speed over time, and partly the visual trick created by a higher seating position. I don't know the people who were in that Sienna, and I doubt they read Road & Track, but since I value my readers and you happen to be right here, I'll take a moment to issue a mild warning:
Be aware of how your speed on the road compares and contrasts with the ability of your vehicle to handle an emergency maneuver at that speed. Both a Sienna and a Huracan Performante can easily reach 100 mph on that long freeway to Vegas. But only one of them is designed to handle a significant cornering load at that speed—and it's not the big white fridge from Toyota.
In the end, we're just over-evolved monkeys who probably shouldn't be driving anything that fast—but human beings are also remarkably bad at assessing risk. We're consistently far more optimistic than circumstances and facts suggest we should be. But you already knew that, right? It's a bigger issue than how fast we drive to Vegas. If we could predict the future accurately, how many of us would go to Vegas at all?