HAVING CRITICIZED Metro's calamitous mismanagement of bus service for the bicentennial weekend, we hasten to applaud the system's impressive performance during the inaugural. Sure, in the morning there was a troublesome door on one train and a brake problem on another. Theodore C. Lutz, Metro's new general manager, is familiar with these two breakdowns - for he got caught in them, too. But on the whole, both above and below ground, Metro moved the crowds swiftly. The on-the-scene presence of Mr. Lutz and all other top Metro officials made an important difference.

Using walkie-talkies and phones, the roving field generals unclogged many intersections, relieved backtips of people at various bus stops and capitalized on the generally friendly spirit in the air. To the amazement of doubting veterans of the Fourth-of-July fiasco, Metro's special bus service worked remarkably well. (The fact that this particular service was offered for free didn't hurt, either.) Except for the car-caused traffic snarls, the special routes run by Metro for the day provided fast paths to and from the main events.

This, of course, is what "rapid transit" is supposed to accomplish in the first place: A bus-rail network can be the most efficient way to get around the city. With the timely opening of the Dupont Circle subway station, for example, a whole set of additional regular bus routes were connected to the subway. The numbers of people that a single subway train can move at one time is impressive, too. The four-car trains in use Thursday - when Metro broke its daily passenger record - were swallowing up 1,000 passengers every five minutes. That's the equivalent of 15 full buses. Moreover, the system here will eventually be equipped to run even longer trains at shorter intervals.

As we all learned so painfully in July, however, the most expensive and well-equipped transportation system can be useless without an alert, prepared management. With detailed planning and a command presence, Mr. Lutz and the reorganized team at Metro passed their first big test with high marks. We hope it was just a taste of what is to come.