Driving in Boston means driving like ass…and driving like ass means you can never be too close.

THE CHALLENGE  The distance drivers allow between one moving car and another is generally referred to as “following distance” and this is how it works in Boston.

Many years ago, I was driving on 2A approaching the Fresh Pond rotary behind some sort of way-cool, Mustang Shelby GT that was tailing a mammoth, early 70’s Cadillac El Dorado at the rage-provoking distance of about 14 inches when the Cadillac came to a stop that must have set some sort of record for distance and the amount of tire tread it left on the road. Needless to say, the Shelby’s reaction time was not up to the challenge. Nor were its grill, radiator, and hood, the latter of which actually detached itself from the car body and—kite-like—sailed off onto the sidewalk. The enraged driver, replete in reflective Ray Bans and a Shelby’s Member’s Only jacket, was out of his car in a flash, explicatives flying, charging the Cadillac which, largely because its gross curb weight in excess of 18 tons, appeared to have suffered nary a scratch. When the Cadillac’s driver emerged, not much smaller than his car and sporting at least two acres of tattoos under his Harley t-shirt, I decided the requisite exchange of papers was not going to be pretty and, having a fair idea of how it would end, I decided keep moving, thankful that it was not I who had been driving like ass.

Rear-end collisions, as often as not, have little to do with brakes or road conditions or the distance between cars. Most rear end collisions occur when drivers simply fail to apply their brakes at all because, sadly, they aren’t even looking. Well, they are looking, but probably at a map or at their cell phone or for that French fry they dropped between the seats last week or at something or someone else. The NHTSA says that rear-end collisions account for 40% of all accidents and, all things considered, that doesn’t sound too bad.

FOLLOWING DISTANCE: HOW IT SHOULD WORK
An oft-lectured driving admonition tells us that, at a speed of 70 mph, a car travels about 100 feet in one second, which is about the time it takes to start a new text message. In Boston, the average distance between cars traveling at 70 mph is approximately 12 feet, so, when you work the numbers, it’s hard to imagine why the roadways are not complete littered with bumpers, headlights, chrome strip, and other detritus from an endless succession of rear-end collisions. In fact, if any single car on Route 128, between the hours of 6AM and 9PM, were to slam on it brakes, it is has been statistically demonstrated that the resulting collisions would involve no fewer than 12,000 vehicles.

But, what makes sense in other states, more often than not, is anathematic in Boston. Tailgating so accepted in Boston traffic that it is presumed that no one would stop suddenly knowing that someone is close to riding up their tailpipe. The type of multi-car pile-ups seen in other, more driver-friendly states are virtually unknown in Massachusetts. Further, NOT tailgating is taken as prima facie evidence that you are either driving too slow, lost, talking on your cell phone, or scared. Ergo, driving like ass.

The distance drivers should allow between one moving car and another is generally referred to as “following distance” —or, to the academics, “time-headway maintenance.” Many drivers learned the “Car Length Rule” from their Phys Ed teachers: a safe following distance was one car length for every 10 miles per hour. However, because visualizing car lengths and estimating distance is considered to be a task beyond the capability of the motoring public, Roadtrip America, a web-based travel site, recommends the “Two Second Rule” which involves pinpointing some fixed point on the road ahead, waiting until the car ahead passes that point, and then counting the seconds until you pass that point. If you get to that point before two seconds, you are said to be too close.

Why this is considered to be easier completely escapes me. Still, I was willing to accept that there was some wisdom in this new approach until Roadtrip America lost any semblance of credibility by further advising “ Here's a tip —drive a mile or two per hour slower than traffic flow. This doesn't cost any appreciable time, and traffic will be slowly pulling away from you, helping you to maintain the space!”…italics, exclamation point, and utter disbelief entirely mine!

FOLLOWING DISTANCE: HOW IT ACTUALLY WORKS IN BOSTON
Most Boston drivers understand that “following distance” has absolutely nothing to do with accident avoidance. Rather, it is a tool by which we: 1) express discontent with the driver ahead, who, of course, is driving like ass; 2) prevent other drivers from moving into the space between you and that driver.

Thus, in Boston, drivers all know that an acceptable “following distance” can be described by the Stepponit—Ghetovmyass formula,
                                                  
which calculates distance (FD) as the inverse of the product of the Aggravation Coefficient (A_c) and Passenger Pressure (P_p), the pressure applied to the floor boards by the passenger, also known as the Sympathetic, or Frantic, Braking Response. The Aggravation Coefficient is an ingenious and complex metric which includes such variables as the number of miles-per-hour below what the following car believes is the suitable speed and the amount of time, in seconds, the following driver believes he is losing by being forced to drive at that speed. The Aggravation Coefficient can be found in tables published by the RMV, although recent research has shown that most individuals have an innate capacity to calculate their specific coefficient on the fly. The explicit, mathematical result of this formula is that as Aggravation Coefficient (A_c) and Passenger Pressure (P_p) increase, following distance (FD) decreases.

Further, astute readers will observe that neither traffic volume nor road conditions influences following distance, as shown by studies carried out during rainy rush hours in Boston. This, of course, is no surprise: the disregard for and indifference to all external conditions is the foundation of driving in Boston and, of course, of driving like ass.