Last week was a bit of a letdown after the thrills we got when the Obamas went traveling. All those good speeches. All those good dresses. A little hug between Michelle and the queen that set off teensy bits of jealousy among the Brits—“Why does Michelle get to hug the queen and we don’t?” It was all in a good cause.

The queen was quite pretty in her pearls and pink dress. She looked a lot like my late mother, which made me like her even more.

But there was one thing that baffled me. The queen greeted the Obamas in what passes as her living room while carrying a pocketbook. My mother never carried a pocketbook in her living room. Do you carry a pocketbook in your living room? I know the queen carries a pocketbook when she is out greeting people. But what is it about that pocketbook that makes the queen of England dangle it over her arm even in her own living room?

In the interest of diligent reporting I decided to contact Buckingham Palace to find out the answer to the last question, but they provided no email address. I thought about phoning, but overseas calls still cost too much. So we will remain baffled on that score.

Instead I began puzzling over a practice even more baffling than the queen’s pocketbook: Why do Boston’s pedestrians have to push a button to summon a walk signal when citizens in other cities get a walk signal without having to do a blessed thing?

And why, in a city in which everything appears to need repair, would anyone in his or her right mind think those buttons work? Moreover, what must Boston’s tourists think when they see Bostonians ignoring the signals and walking anyway.

So I went right to the top and asked Jim Gillooly, Boston’s affable Deputy Commissioner of Transportation, why Boston needs buttons. He said the buttons are there so a walk cycle will not delay traffic if there are no pedestrians waiting to walk. “Traffic is being handicapped unnecessarily,” he said.

This practice reduces pollution and decreases driver frustration, he said.

That makes sense on a large roadway where there are few pedestrians, and I admit I have seen buttons in other cities at such locations. But in Boston it would be hard to name a downtown intersection where there are no pedestrians waiting to cross. Gillooly acknowledged that, but he said late at night, for example, there is no need for cars to wait when there are no pedestrians around. Point taken.

But that still doesn’t answer the question of why Boston is the only city in North America—maybe the world—that takes that point of view.

The answer appears to be that Boston may be the only city in the world that does not favor “concurrent” pedestrian crossings. Concurrent means that traffic and pedestrians both have a green light to cross an intersection at the same time going in the same direction.

Gillooly said Boston’s one-way streets and complex street patterns mean that concurrent pedestrian and traffic crossings intersections aren’t as safe here.

That’s another bafflement. We all know Boston drivers are crazy, but do we really believe Boston drivers making a turn would mow down more pedestrians than, let’s say, Chicago or Cambridge drivers—especially if there were a sign telling them to give way to pedestrians in the cross walk, and also if a police officer were to hang around intermittently at choice locations to ticket potential mowers?

Cambridge took away buttons a few years ago, deciding it was safer to give pedestrians the concurrent walk phase, said Sue Clippinger, Cambridge’s Director of Traffic, Parking and Transportation. Her staff felt that pedestrians made impatient by waiting were more likely to take risks. In addition, Clippinger said that concurrent signals typically reduce the wait time for drivers also.

WalkBoston, the pedestrian advocacy group, has tried to persuade the city to make more crossings concurrent, and Gillooly said the percentage of concurrent walk signals is up to 25 percent from about five percent a decade ago.

Moreover, Gillooly said that about 30 percent of the 450 signals connected to the city’s electronic Traffic Management Center have an automatic pedestrian phase during times of day when they are most needed, so you don’t really need to press the button.

That probably baffles pedestrians even more, since they have no idea those intersections exist or where they are or what they need to do.

So not knowing what to do or where, Boston’s experienced pedestrians walk across the street whenever it feels like a good time to do so. The system may be baffling, but maybe it actually works pretty well.