TRUE TO formlessness, Monday's first-ever public hearing by the new D.C. Taxicab Commission was like the hacker you hate to hail: loud, freewheeling and slow to get to any point. As on the streets, rude cabbies tended to upstage those who are working for improved service in the capital city -- but the commission does seem intent on making a constructive difference. A number of get-tough measures already are in the works, and the new crackdown should not be detoured by the wails of a minority who fear it. But there is one proposal that keeps being mentioned as a "reform" that should be rejected: a limit on the number of licenses.

There is no reason whatever to believe that by keeping the business clubby you'll get better service. On the contrary, good competition -- among drivers who are thoroughly qualified and who are operating safe vehicles in an honest fashion -- should help, not hurt, the market. Closing the industry at some arbitrary number would simply deny jobs to people willing to compete. Gregory Brooks, who said he is preparing to become a cabdriver, made the right distinction: "I have no problem with stringent regulations on getting a license," he commented, but "I do have a problem with not being able to get one at all."

More important right now is the number of unlicensed drivers still cruising the city in dangerous vehicles, with no knowledge of the terrain and no regard for the rules. Paul Davis, one driver who has been urging a crackdown, termed this a "very serious, terrible problem. It makes it harder for us to go out and compete and make a living under these circumstances."

Washington has to field more hack inspectors, and the commission is moving to do so. In the meantime, stiffer fines and a more efficient complaint process should begin to curb some of the worst offenses. Good, honest cabdrivers should be eager to support this weeding -- as this city's battle-weary passengers surely are.