So I was strolling Market Street late one afternoon last week and, as always, traffic was a mess. Cars clogged intersections and crosswalks. Buses honked, pedestrians fumed. Gridlocked commuters sat helpless at the wheel.

Then, in a flash, inspiration hit.

Bring back the Embarcadero Freeway!

What could be more convenient for bridge-bound drivers than to ascend at Broadway or Clay Street and glide along the waterfront above city streets? No more confusion for commuters where two grids collide, and everyone else will have an easier time with all those automobiles moved offstage.

Sanity returned and I reminded myself that the removal of the Embarcadero Freeway, the 1990 demolition of the two concrete decks after 31 inglorious years, was one of the smartest things the city ever did.

But that moment of connect-the-dots madness drove home two blunt points. First, there are no easy solutions to large urban problems. Second, a logical analysis of those problems can be taken to ruinous extremes - as was the case in San Francisco and other American cities in the years just after World War II.

The challenge then and now is that the city's northeast corner has two street patterns that meet at Market but make no sense from an automobile standpoint. Some north-south routes connect cleanly. Some connect with a jog. Some don't connect at all.

On Market Street itself there are cars - though if some city bureaucrats get their way that will change - and buses. And historic streetcars. Pedestrian throngs, and a bicycle contingent that seems to grow by the week.

One big snarl

All this translates to a snarled scene that isn't much different than when Miller McClintock pondered the "Market Street Crossing Problem" in, wait for it, 1937.

McClintock was a traffic consultant of nationwide renown; San Francisco was a city with new bridges to the north and east and a whole lot of traffic in between. The expert told the locals to make drivers happy, or else: "Unless the average person finds freedom to go where he wishes, when he wishes, with minimum delays and by routes which are direct to his destination, the attractiveness of the central district is reduced."

Like any traveling salesman, McClintock had his remedy close at hand - "the removal of hazardous and congestive movements of through traffic," which in turn would make San Francisco "the first American city to achieve a reasonably complete and permanent solution of the pressing problems of traffic accidents and traffic congestion."

Can't argue with that, right? Except that McClintock's "comprehensive Limited Way Plan" in retrospect was - let me find the diplomatic term - insane.

Here's one example: An elevated path from the Bay Bridge ran above Kearny Street and continued above Columbus Avenue. Van Ness Avenue got the same treatment, though McClintock suggested that near City Hall "the elevated Limited Way should be given architectural treatment consistent with the monumental character of the existing structures in order that it may blend."

No mere hallucinogenic fantasy, McClintock's 460-page vision was commissioned by the city's Department of Public Works. Its approach to transportation segregation influenced the city's official Trafficways Plan of 1950 - including, yes, ramps that whisked Financial District workers around Market Street to the Bay Bridge by way of the Embarcadero, which then was a working port.

Unthinking destruction

Again, the move made sense when viewed as an exercise in traffic engineering. It's only when you appreciate that cities are fluid, fine-grained landscapes that the unthinking destruction - cultural as well as physical - snaps into focus.

When ordinary citizens saw how the Embarcadero Freeway severed the Ferry Building from Market Street, the crude concrete swath was halted at Broadway. The 1989 Loma Prieta earthquake created an excuse for the double-deck structure's removal, and now the Embarcadero is a treasured promenade along the bay. Many Bay Area residents probably don't know it ever was burdened with a freeway at all.

Can Market Street blossom as well? Perhaps. The city's Better Market Street effort aims between now and 2015 to conjure up a boulevard that "is more beautiful and green," where "all users have a pleasant, reliable, efficient and comfortable experience."

The only catch is all those cars. Even if private automobiles are banned from Market east of Van Ness - an option put on the table this week as part of Better Market Street - they'll still be funneled south onto First, Fourth, Eighth and 10th streets. North on Fremont, Third, Seventh and Ninth streets.

"Market Street is the constrained capacity point in the city," says Jeffrey Tumlin, author of "Sustainable Transportation Planning: Tools for Creating Vibrant, Healthy and Resilient Communities."

Tumlin's experience as a transportation consultant is that if 10 percent of drivers opt for other means of travel, most of the gridlock goes away. He explains how Muni would be a more attractive option if bus-only lanes actually were bus-only, for instance.

Realistically, though, our ever-expanding and increasingly busy downtown will never be bucolic. "There's likely nothing we can do to eke more capacity out of the street network," Tumlin says. "The question is how can we best manage what we have."

In other words, today's Market Street is the world we have chosen for ourselves. Not a pretty picture. Still, I'll take it over an elevated world that almost was.