Sometimes it seems that no matter how much progress is made toward racial sensitivity in this country, there remains a chasm as yawning as the Grand Canyon.

After all of the uproar over the Greaseman (aka disc jockey Doug Tracht) and his slur against the memory of the Rev. Martin Luther King Jr., it would make sense for public figures to be on guard against insensitive public statements. But the other day, a liberal, even progressive member of the Congress recounted a joke that was in extremely poor taste.

Tracht's comment about the King holiday -- "killing four more" blacks would result in getting the rest of the week off -- appalled and angered many Washingtonians.

In the aftermath, Tracht lost some of his sponsors, and a Howard University student organization called the Black United Youth has demanded that DC 101 take him off the air. Although the station management offered to suspend Tracht, who has apologized for the remark, the furor goes on, and it is being watched by many radio stations.

Meanwhile, on Feb. 5, several postal-related subcommittees were holding hearings on Capitol Hill on the subject of the firing of Postmaster General Paul Carlin and the appointment of his replacement, Albert Casey.

At one point, Rep. Mervyn M. Dymally (D-Calif.) asked questions about affirmative action in the Postal Service.

Rep. Patricia Schroeder (D-Colo.) said later that the questions about affirmative action "struck a bell in my head" because it reminded her of a "very sick joke going around town" during the Super Bowl. "I think it had a lot of truth in it, and the post office was part of the joke."

Schroeder said: "The question was, 'What do you call one white man surrounded by 10 blacks?' And the answer was, 'Coach.'

"And it was then, 'What do you call one white man surrounded by 100 blacks?' And the answer was, 'Warden.'

"And 'One white man surrounded by 1,000 blacks' was 'the postmaster.' "

Now Patricia Schroeder is about as different from Doug Tracht as night is from day. Whereas Tracht has a reputation for regularly offending different ethnic groups, Schroeder is a sensitive, progressive liberal.

Moreover, Schroeder not only threw in the caveat that the joke was "sick," she also made her comments in the hope of achieving a positive end -- a greater representation of blacks in positions of authority in the Postal Service.

But as Scott Joplin says in the opera "Treemonisha," "Wrong is never right," whether it comes from a conservative, a nincompoop or a progressive.

Part of the problem with recounting such jokes in public is that, despite many signs of progress, race relations in some respects have taken a negative turn during the Reagan administration. Although there is no doubt that Schroeder has conquered more prejudices than most, it still demeans her to resort to such "jokes" to make a point, and it further unravels the frayed fabric of racial harmony.

Despite the overlay of progress, many segments of society remain a social powder keg. One way to defuse that explosive potential is for everyone to exhibit fairness and sensitivity toward each other.

Many Washingtonians, especially the students from Howard, would like to see the Greaseman resign.

Make no mistake about it, Schroeder is no greasewoman. But the remarks she made at that hearing should give us all pause, and she should stop and think the next time a situation "rings a bell" that brings on a joke that may be deeply offensive to many people in the city.