After nearly a decade of controversy the results are finally, physically in place on the 2000 block of I Street NW, where a clean-lined, 10-story office building forms a massive horizontal backdrop for the restored 19th-century houses affectionately known, at the furor's height, as the Red Lion Row.

The project is a triumph of sorts. Had preservationists, students, critics and reviewing agencies not forced the issue, George Washington University, the principal developer, would have flattened Red Lion Row (a nickname adopted from a tavern that occupied one of the houses) without a backward glance.

So, instead of a block-long behemoth office building facing the street we have a block-long, behemoth office building rising behind the 19th-century houses, which are being converted for retail and office uses. This compromise is by no means the most sympathetic solution to the omnipresent problem of relating new construction to valued antiques, but it is far better than the bitter alternative of demolition.

What has been saved is significant. The houses along the row are a varied lot, ranging from restrained late Federal and Greek Revival structures to exuberant Victorian pieces. No one of the buildings is a masterpiece but together they represent a cohesive reminder of the scale, texture and style of the 19th-century city.

Still, the main deficiencies in the design of the new package are severe and fairly obvious. The new building is too big, it is too close to the 19th-century houses, its massing is insufficiently modulated, and its style, though reminiscent of the university-built office buildings that flank the site, is thoroughly unrelated to that of the foreground structures.

John Carl Warnecke, the project's principal designer (working in a joint venture with Hellmuth, Obata and Kassabaum) and architect of the relatively successful solution to similar problems at Lafayette Square, states that his intention was to build a "quiet" structure, "one that would not call attention to itself, but would form an unobtrusive backdrop for the old buildings."

The exterior is, as he says, "free of embellishments or eye-compelling textural features," but the only place from which it is unobtrusive is from the sidewalk in front of the 19th-century row, where it cannot be seen at all. This is, of course, a big plus, and one that will become bigger should the city accept the university's application to close the 2000 block of I Street to automobile traffic.

But from the north along Pennsylvania Avenue, which will remain the primary image of the place, the indelible vastness of the building, its tremendous horizontal sweep, is overpowering. The looming presence of the structure, with its light skin of pinkish precast concrete panels and long window courses of blue-tinted glass, does indeed increase one's awareness of the attractive lower buildings in front of it, but in a curious way: They take on a flat, stage-set, Potemkin village appearance. (A trusted adviser to Catherine the Great, Potemkin erected spanking new false-front villages to impress his monarch on her trip through southern Russia in 1787.)

It is an ironic deception, unfortunately making the project look as if it involved just fac,ade preservation. In fact, one of the felicities of the final design, thanks mainly to the vigilance of student preservationists, members of Don't Tear It Down and the Joint Committee on Landmarks, is that the older buildings were preserved to their full, original depths (retaining, where possible, their original rear and sidewalls, which were dismantled during construction and then rebuilt).

Besides allowing us a fuller (though obviously not pure) experience of the original buildings, this strategy made possible the forming of an extremely interesting, glass-roofed courtyard connecting the old buildings to the new. Running the entire length of the office building, varying in height from three to four stories and in width from about 15 to 40 feet, with connecting ramps at each level and a constant contrast between concrete surfaces and pillars on one side and brick walls on the other, this space, though tight, is a major redeeming feature.

Tenants have begun to occupy the upper floors of the office building, but the courtyard space will not really come alive until April, when the restaurants and retail stores move in. There may be as many as 60,000 square feet devoted to these uses (nearly the same amount as in the Old Post Office) and there is no question that the space will become a welcome concentration of small-scale commercial life in the long stretch of Pennsylvania Avenue between the White House and Georgetown.

Though there is a pedestrian connection through the office building from the avenue to the main university quadrangle--something that has long been needed--it is neither clear nor dramatic. Since the main building reads as a wall, people are left pretty much on their own to locate the pathway. People who need to will find it, no doubt, but one can't help concluding that a great opportunity to make a visible, symbolic gateway linking the city and the school was lost here.

The 2000 I Street project (understandably referred to by its owners as 2000 Pennsylvania Avenue) takes up about half of the city block bounded by H, I, 20th and 21st streets. George Washington University owns most of the remaining portions of the block. Had university officials been willing to give up some density (as the National Geographic Society did with its new building) or, more creatively, been willing to develop the block as a whole as part of a longer-term, phased project, the architects would have had a much better chance to design a distinguished product.

Half a loaf is better than none, it's true, but despite its redeeming qualities 2000 I Street stands less as an example of the art of architecture than as a simple, direct, clear statement of the built-in conflict between conventional zoning and preservation.