The only thing more fashionable than Madonna these days is beating up on Amtrak. The raps are as tedious as they are familiar: crummy service, employes who don't care, nobody walks the extra mile, blah, blah, blah.

Well, blah is what I say to all that after talking to Roger Conner the other day. He had just placed himself at Amtrak's mercy -- and our national chuggistry came through with flying colors.

Roger is the head honcho at the Federation for American Immigration Reform. His assistant director for finance, K.C. McAlpin, was scheduled to go to Newark, N.J., last Monday morning for a budget meeting that afternoon. But just as K.C. was boarding a 9 a.m. Amtrak train at Union Station, the meeting was abruptly cancelled.

How to get word to K.C. to turn around and come home? Roger called Amtrak. An operator told him that a message would be passed along. But as Roger puts it, "Cynicism was just dripping as I hung up the phone. Somebody in the office said, 'You know they'll never do it.' "

But do it they did. As K.C.'s train pulled into Baltimore at 9:35, he heard himself being paged over the loudspeaker. K.C. confessed to a conductor that he was indeed K.C. Whereupon the Baltimore stationmaster came aboard to deliver the come-home message personally. K.C. was back at his desk in D.C. by a little after 11.

Lessons? Well, there's a certain Washington lobby that won't be flying to Newark the next time there's business up thataway.

Speaking of lessons, you would have thought that proprietors of local Chinese restaurants would have learned from a celebrated 1983 episode. Evidently, not all have.

Two years ago, the Szechuan Garden Restaurant on Connecticut Avenue was sued by three black women. The women claimed that the management arbitrarily added a 15 percent service charge to their luncheon check. According to court papers, when the women asked why, the manager told them it was because "you people never tip."

That remark cost the Szechuan Garden a $21,000 out-of-court settlement. Now comes exactly the same story -- and the threat of another lawsuit -- involving a Chinese restaurant downtown.

Annette Walton of Northeast, a black woman, ate lunch there with two other black women on June 12. The same 15 percent was added to their check, without warning or without any notice published in the menu. Annette told me she asked her waiter why, and was told, "Because you all don't tip."

"What do you mean, 'You all?' " Annette says she asked the waiter. He simply repeated, "You all don't tip." After some angry words, the waiter said he would cross out the service charge "this time," and he did so. Still, Annette says that she and her two luncheon mates are considering a lawsuit.

I'm not going to name the restaurant, for two reasons: First, I run a column here, not a courtroom. Second, management says the waiter acted on his own, without its blessing or knowledge.

But to the other restaurants in River City, Chinese and non, this reminder:

A tip is a privilege, not a right. If you are going to add a 15 percent service charge, you must do it to every check. Otherwise, you're using the service charge as a bigoted bludgeon. That is bad business -- and even worse human relations.

Bill Burger of Frederick raises a point that has long been rattling around in my brain: How does Washington stack up against other cities in terms of rush-hour cars occupied by the driver only?

Bill sees plenty of driver-only cars in the course of his week. He drives toward Washington during the late afternoon. Coming the other way on Interstate Rte. 270 is a daily sea of solos. As Bill notes, if only half those cars contained somebody else, both traffic jams and cries for more highways would quickly subside.

Unfortunately, Bill, I have bad news for you.

Believe it or not, Washington has the second best solo-driver ratio in the country.

Here are the latest figures drawn from census data and provided by the Washington Metropolitan Council of Governments:

New York: 31 percent of all cars at rush hour contain the driver only.

Washington: 54 percent.

Boston: 56 percent.

San Francisco: 58 percent.

Chicago: 58 percent.

Philadelphia: 59 percent.

San Diego: 64 percent.

Denver: 65 percent.

St. Louis: 67 percent.

Cleveland: 68 percent.

Los Angeles: 69 percent.

Houston: 70 percent.

Dallas: 71 percent.

And Detroit: 75 percent.