bumps in the road

You drive along a city street, east or west, north or south; it doesn't matter. It might even be a suburban roadway, though not a country road or highway. The vehicle in front of you suddenly swerves to the right, or left, a reactionary maneuver. Is it to avoid hitting a pedestrian in the roadway? A squirrel daring to risk its squirrelly life by threading in, around, or through the moving onslaught of tires that would crush it and extinguish its life? Perhaps the driver in front of you and subsequently you are dodging a sharp object in the road, an object potentially injurious to your tires, and to you and your occupants. Maybe it's a squirrel or woodchuck or bird or rat or raccoon that did not make it to the other side of the roadway, entrails still steaming, flies not yet settling to feast on the corpse. Let's not omit the possibility that it's a human, injured or having reached his or her expiration date, in the busy roadway.

No.

It is none of these.

It's a bump in the road. More accurately, it's the opposite of a bump in the road, whatever that would be called.

The current trend is to dodge, swerve, steer, veer, zigzag, weave, or pivot a vehicle away from the depression of a utility or maintenance hole cover, also known as a manhole. Sometimes, though not as frequently, the cover is raised slightly above the surface. More often, it's below grade, causing unswerved tires to drive over a depression of, what?, 2 or 3 inches max.

Fortunately, the vehicle in front of you merely swerves, like an Olympic skater, rather than slams on the breaks and stops.

You wonder why this trend exists. You consider that each vehicle exercising this transportation mode might be transporting a sleeping child or two in a car seat, and that said child or children might awake, screaming, owing to the less-than-earthquake-intense disturbance. You also consider the notion that a teenager or teenagers riding in the vehicle, earbuds or headphones in place, might, as a result of driving over an indented maintenance hole cover exclaim, "Whatthefuck, Mom. I'm trying to do my English homework here!" 

Or you may not be remotely aware of The Veer at all.

You find it puzzling. It baffles you.

Is this vehicular maneuver limited to vehicles with tires apt to burst, thereby making it imperative for the driver to dodge the utility hole cover?

No, you find that cars sporting expensive, sturdy, resilient, top-of-the-line tires perform this aversion tactic as much as any vehicle with no-tread tires, with tires on their last rubbery legs. 

Is it limited to older cars with lousy shock absorbers?

Au contraire.

Vehicles featuring the latest shock-absorbing, quietening technologies known to humankind are as apt to perform the maneuver as anyone else.

You stop and think: how long has this been a common habit of drivers?

Is it limited to specific geographical regions, drivers with certain income levels, age, education, upbringing, class, religion, lack of religion, occupation, gender, or other defining characteristic?

None that you can discern.

Really: why does that driver in front of you execute The Swerve?

No one seems to know.

Vehicularis interruptus.

It could be a contagion, a broadened application of pothole avoidance.

It might be some vast conspiracy aimed at the local DPW.

Can any conclusion whatsoever be drawn from this ubiquitous (at least in my environs) custom?

Is there any broader lesson, metaphor, or moral that we can draw from this practice?

Is it a far cry, an absurd stretch, to suggest some sort of aversion to jostling, displeasure, or inconvenience?

Or does it posit no meaning whatsoever?

Inquiring minds want to know.