A shared bike on a shared road: It’s part of the “Street Smart” future envisioned by “Gridlock Sam” Schwartz in his new book. (Molly Riley/AP)

These are two of the lessons I got this year on the power of travel habits:

1. In the days before the pope’s visit in September, I heard from many locals and out-of-towners who were concerned about getting around the capital, given the congestion and delays we expected.

They asked about their options for routes and travel times. But there was one option that very few considered: getting out of their cars.

Despite everything they had heard, they really wanted to drive. It wasn’t that they remembered bad experiences with Metro, or felt incapable of using a bike or walking. Driving is what they did, and what they were going to do.

We celebrated the lack of congestion while Pope Francis was here, but it wasn’t so much that people changed their travel habits as that so many stayed away from their downtown offices.

2. During this year’s debate about Virginia’s plan to put high-occupancy toll (HOT) lanes on Interstate 66, I’ve heard from many people disappointed with the plan not so much because it would toll some lanes, but rather because it doesn’t greatly expand the space they have to drive by themselves.

These two lessons were on my mind last week when I spoke with Samuel Schwartz, who as a New York City traffic engineer helped popularize the word “gridlock.” (The term came into widespread use because of a 1980 transit strike, which was accompanied by warnings about what would happen if everyone turned away from the subway chose to drive into the city’s grid of streets.)

“Gridlock Sam” eventually left government service to set up an engineering and consulting firm that advised on transportation projects around the world. He recently wrote a book about the past and future of urban transportation, “Street Smart: The Rise of Cities and the Fall of Cars.”

You get the idea that Schwartz foresees a world that’s very different from the car culture he and I grew up in.

“See the USA in your Chevrolet,” he quoted to me, from the dim mists of 20th-century advertising.

Schwartz, who was born in 1947, was trained along with other transportation engineers in how to move cars. But over the decades, he has developed an expertise in moving people.

“My first career was about increasing capacity — squeezing more cars into the same amount of space,” he said in a phone interview from his New York office. “The quality of life didn’t get any better. That’s when I began to see the futility of it.”

During the debate over HOT lanes, I’ve talked with many people who complain that the government is trying to manipulate their commuting behavior.

Schwartz notes that home-loan guarantees favoring construction of new homes, along with the heavily subsidized network of superhighways connecting cities and far suburbs, amounted to a federally sponsored ma­nipu­la­tion of the post-World War II transportation system.

The urban superhighway network was over-engineered, partly because the planners and engineers didn’t have the tools available today to create a friendlier, more efficient system that gives people more choices about how to get around.

Schwartz, who co-wrote the book with William Rosen, is talking about better-organized communities and about travel in shared vehicles, rail and bus transit, biking, and walking.

This may sound to some like transportation ideology, but in Schwartz’s Futurama, the private auto isn’t going to disappear.

“It wouldn’t be practical even if it were desirable, which it isn’t,” he writes. “A car-free future is a myth: seductive but unreachable.”

Still, Schwartz highlights all those transportation industry studies that calculate the multitrillion-dollar cost of modernizing our postwar transportation system. And he asks why we’d want to invest the nation’s treasure in shoring up a 20th-century system when we have the tools to create a smarter one that’s tuned to the way people are going to want to live for the rest of this century.

The transportation system he describes — a system already evolving in many urban areas, including here in the capital — consists of multiple methods of getting around, methods that intersect at many points. We won’t “depend on a single form of transportation or a dominant core to which all routes lead,” Schwartz writes.

The system he describes is more complicated. You don’t just get in the car, go, then find a place to park. That’s why information, readily available to travelers, emerges as the key to Schwartz’s “Street Smart” city.

He is counting a lot on the millennials, the generation that grew up comfortable with technology, mobile communications and active effort in getting around. The new transportation system is a good fit for their lifestyle.

I don’t see other generations aging out of the U.S. transportation system. But why stick to the well-traveled path, just for the sake of familiarity, when new opportunities are arising?

Dr. Gridlock also appears Thursday in Local Living. Comments and questions are welcome and may be used in a column, along with the writer’s name and home community. Write Dr. Gridlock at The Washington Post, 1150 15th St. NW, Washington, D.C. 20071, or ­e-mail drgridlock@washpost.com.