OF ALL THE CONS perpetrated on the American consumer, none amazes me more than the U.S. Postal Service's humongous ad campaign -- $301 million last year, to be precise -- and the accompanying cosmetic changes designed to convince us that a hapless, surly bureaucracy is actually efficient and friendly.

So I was most cheered not long ago when I witnessed not one, but two actual customer revolts at my local post office. Friendship Station in Northwest was a fairly spiffy post office before last year's $260,000 renovation, which made it an ultra-spiffy post office. But while the Postal Service moguls were pouring money into the latest wall graphics and ever more glaring light, they apparently forgot to add actual personnel.

The result: queues that stretch out the front door, even on weekdays. This is true at tax time or no particular time, Christmas rush or summer lull.

But the renovation did accomplish one thing. By creating a separate counter for customers who want only to buy stamps, the Postal Service ensured the presence of an idle worker who joins fuming customers in gawking at the endless line. Could this stamp seller help the lone worker handling the line of 35 customers? Not a chance, says Bill Miner, acting postmaster for the District of Columbia. "For security reasons, that person has to stay at the stamp counter."

One lovely morning, I'm toward the rear of a line of about 20 people waiting for service while a solitary clerk takes his time. A nicely dressed gent carrying a small package finally goes, well, postal. He begins to clap rhythmically, the kind of beat you might hear during a rally at a ballpark. The elderly woman ahead of him joins in, and then others, and soon half the line is into it.

The stamp seller rushes out from behind her counter, where no one waits. "If you only want stamps, you don't have to wait," she calls out. But we knew that already.

"Why don't you go over there and take packages?" a young woman says, rather nastily.

"I work the lobby counter," the clerk says haughtily. The clapping continues.

Finally, the lone clerk inexpicably disappears backstage. Some customers leave, some trade post office horror stories. Only the man who began the revolt keeps up his protest.

Another morning, some weeks later: another long line, this time served by two clerks (the other three windows seem to exist largely as a tease). This time, a middle-aged woman steps out from mid-line.

"How long do you expect people to wait?" she asks a clerk, sharply. "Doesn't anybody else work here?"

The clerk, cornered, snaps: "People just call in sick all the time. People don't care, they don't come to work, what am I supposed to do? They need more people here, but I don't do the hiring."

Their exchange loosens the floodgates. Others in line shout complaints, suggestions, wordless exclamations. But nothing happens. Again, some folks bail out.

"Exciting times at the post office," Deborah Yackley, who handles PR for the Postal Service's Capital District, says when I relate the incidents. She's stunned that things aren't hunky-dory at the just-renovated office: "I was there at Christmas, and everybody seemed happy and smiling. People really like the bright new colors."

She puts me on hold. A gentle guitar serenades me, giving way to a recorded voice asking me to behold the marvels of the Postal Service: "It's simple, it's convenient . . . "

Yackley returns with an explanation. "We operate as a business and we try to eliminate the waste," she says. "We try to make sure we don't have too many people around." They're doing a bang-up job in that regard.

I suggest that more than one clerk might be needed to serve a vast urban neighborhood. Yackley checks in with Friendship Station's operations manager, who won't actually speak to me, but passes on this assurance: "There just don't seem to be enough clerks and they're considering putting up some additional positions."

That sounds splendid. So do the assurances of a raft of guardians of the Postal Service's image, who call me repeatedly to describe, as spokesman Roy Betts puts it, "Americans' love affair with the Postal Service."

Bill Miner tells me how he uses "mystery shoppers" and lobby cameras to monitor service. "I'm going to follow up there with more mystery shoppers," he promises. The Postal Service is committed to total customer satisfaction. In my mind, I hear that guitar serenade again.

Miner tells me about a new Postal Service initiative called Service in Five Minutes or Less. I like that. I call the woman in charge, Barbara Ford.

She doesn't sound pleased to hear from me. "Did someone refer you to me?" she asks.

Suddenly, I'm on hold. Then, "Can I call you back?" she asks icily.

Five minutes pass. Then five hours, five days. She never does.

Marc Fisher's e-mail address is fisherm@washpost.com.