Let's say you bought this car, a Cadillac CTS-V Sport Wagon, with a 6.2-liter, 556-horsepower Corvette V8, six-speed manual transmission, magnetorheological dampers (I'll get to that), Michelin SP2 gumballs, 15-inch front Brembo brakes with six-pot calipers, and microsuede wrapping on the steering wheel and shifter. Well, first of all, you'd be one strange cat, which is to say, unusual. Notwithstanding any nitro-burning ice-cream trucks or flying boattail Rollses in your neighborhood, this wagon is about as esoteric an automobile as you're likely to find. Statistically speaking, General Motors will sell exactly none of these cars, the Detroit equivalent of Zoroastrianism.

Photos: The 2011 Cadillac CTS-V Sport Wagon

But if you did buy one, what would you do with it? You'd have a lot of options. Like Cadillac's 3.6-liter CTS wagon—with a mere 304 hp—the V-Wagon has a useful and accessible 22 cubic feet behind the rear seats and a generous 56 cubic feet with the second-row seats folded. Among other things, you could take three weeks' worth of groceries to the test-and-tune session at your local drag strip. Zero to 60 miles per hour in this car goes by in 4.3 seconds—such acceleration momentarily takes years off your sagging jowls—and then the car really starts to move, thundering through the quarter-mile in 11.9 seconds at 116 mph, according to my colleagues at Car and Driver, who do impeccable instrumented testing.

Such a car would be useful if you wanted to duck car-pooling duty or avoid field trips with the Cub Scouts, because no child emerging weepy and jelly-kneed from the back seats of this supercharged washing machine will ever want to get back in. You'll be on cupcake duty from then on.

You could attempt to redeem yourself for such an automotive purchase, as you should. The V-Wagon is utterly, cosmically and seismically wrong, a filthy, shameful ogre of torque that bellows and sets alight thatched roofs as it drives by—Caliban with pushrods. You owe God or somebody an apology.

2011 Cadillac CTS-V Sport Wagon Cadillac Price as tested: $63,465

$63,465 Powertrain: Supercharged and intercooled 6.2-liter pushrod V8; six-speed manual transmission; rear-wheel drive with limited-slip differential

Supercharged and intercooled 6.2-liter pushrod V8; six-speed manual transmission; rear-wheel drive with limited-slip differential Horsepower/torque: 556 hp at 6,100 rpm/551 pound-feet at 3,800 rpm

556 hp at 6,100 rpm/551 pound-feet at 3,800 rpm Curb weight/length: 4,390 pounds/191.3 inches

4,390 pounds/191.3 inches Wheelbase: 113.4 inches

113.4 inches 0-60 mph: 4.3 seconds

4.3 seconds EPA fuel economy: 14/19 mpg, city/highway

14/19 mpg, city/highway Cargo capacity: 22 cubic feet (behind second row). 56 cubic feet (rear seats down)

Perhaps you could put on demonstrations for the local high-school physics club, using the g-meter built into the car's instrument cluster to show exactly what more than 1 g of lateral acceleration feels like. It feels like a fat lady is trying to push you out the side window. Or if not physics, the Greek club, since like Antaeus the V-Wagon maintains an Olympian grip on the earth and draws strength from it. Maybe you could help out at the police training range, letting cadets chase you to improve their hot-pursuit driving skills. Then, having been completely demoralized, these plebes will quit to become firemen. The world needs firemen.

What you couldn't do is volunteer to rush transplant organs to faraway hospitals, because if you did, you'd only arrive with coolers full of gazpacho.

This then, is a fast car, and a useful car (sort of), and a surprisingly affordable car, with an MSRP of $63,465, exactly the same price as the CTS-V Coupe—which itself is an odd fact, since the V-Wagon weighs 200 pounds more than the coupe and, even if you only measured by the pound, you'd expect it to cost more.

All of these notions—the car's price, its perversely limited appeal, its supercar limits, its utter unsuitability for the very missions it would seem tailor-made for—add up to one thing: This car is pure marketing.

The only people who will want this car are people like me, dizzy enthusiasts and car lovers, but more than that: car reviewers. Car reviewers cycle in and out of dozens of new cars every year. We buy not, neither do we lease. And because of that, we can afford to fall in love with a snot-flinging rodeo bull like the V-Wagon (or cars like the now-defunct Dodge Magnum, the Audi RS6 Avant, Mercedes-Benz E63 AMG Estate or the Europe-only BMW M5 Touring). If we were spending our own money, we might reasonably ask why a station wagon needs to be faster than a mid-1990s Lamborghini. Is it likely I'm going to uncork this bottle of hateful Champagne in the bank drive-thru?

Likewise, if we're scribbling our own check, we might think, "Well, if I want a sports coupe, shouldn't I get the model with two doors?" This is particularly apposite in the case of the Cadillac, since the CTS-V Coupe is, I think, the best-looking, most daring American car since the Auburn 852 SC Speedster.

Here's the lick, though: People in my position are easily bored. The gliding gossamer ride of a BMW 7-series is astonishing, that's true, but the miracle moment slips away as the days pass, and the car begins to feel trifling and sedate. A Ferrari 458 Italia is the best sports car in the world, but where am I going to put my golf clubs or even my golf trophies? People in my position are fussy pains in the butt, really.

The V-Wagon answers the auto reviewer's lament: Why can't I have everything and why can't it be interesting?

For Cadillac and GM's part, the calculation is simple: It costs a few million to develop this, the last and best riff on the CTS, and building it guarantees endless buff-book magazine covers; dozens of YouTube videos featuring the V-Wagon performing fluffy, white cumulonimbus burnouts; and miles of adoring type online and in print. Does it work? You're here, aren't you?

And by pricing the V-Wagon the same as the coupe, the company didn't even bother to disguise its lack of interest in a margin. Who cares? It all comes out of the marketing budget.

In a way, it's encouraging. GM is getting its mojo back, playing the game, rousing the faithful. You have to love it.

And the V-Wagon is, above all, interesting. Where to begin? With the "World of Warcraft" mesh grille; the fractal insanity of the styling? What about the fact that, in addition to a six-speed automatic, this wagon can be had with a six-speed manual transmission, a device that's quickly becoming a drivers-only shibboleth? No ladies' clutch nor vague shift gates here. The clutch throw is heavy, the uptake sweet and progressive. The gearbox has the momentous, latch-in-place action of a switch for an electric chair. Slot it into first, ramp up the revs to 4,000 and slip the clutch. The lights in your brain dim like it's midnight on the Green Mile and wherever you were, you ain't anymore.

Like the Corvette ZR1 and the CTS-V Coupe, the wagon is set up on magnetorheological dampers, which use micro-metallic particles in the dampers to vary viscosity according to the car's dynamic sensors. The result is an easy and composed ride in daily driving, and the ease and composure doesn't diminish as you start to throw the car around. The front tires take a huge bite on turn-in, the car barely rolls and then it burrows into a corner like a tick. This car has no bad habits, particularly as you approach the limits of tire adhesion. Like the V-Coupe's, the V-Wagon's stability-control system has a sport map, and once engaged, it makes it hilariously easy to rotate the car under power. This thing is the drifting king of your kid's preschool porte cochere.

From the tuft of its excellent Recaro seats to the melty rubber bits under the tires, the V-Wagon is illicit, overpowering, sexy and a touch scary. If it were boxing gloves it would be banned by the Nevada State Athletic Commission. I recognize to love it is to be played a bit by GM's marketing guys, but I don't even care. The V-Wagon is never boring. That's all I ask.

Write to Dan Neil at rumbleseat@wsj.com