Some merchants will observe the opening of their newest store by talking at length about their point-of-sale terminals, their sales per square foot and return on investment or the latest innovation in circle racks.

Joseph E. Brooks, chairman of Lord & Taylor, is not one of those.

In Washington for the debut today of the latest Lord & Taylor, at Fair Oaks Mall, Brooks talks about style, taste and his favorite expression, "point of view."

"You show me a company that does well and prospers and I'll show you a leader who has a point of view and maintains it.

"Lord & Taylor has a very definite point of view. . . We stick to it. . . We know who we are. . . You must constantly update in this business, but you must always maintain your point of view."

What Lord & Taylor is, is a highly succesful specialty retailer that in the five years since Brooks became chief executive has jumped from 21 stores to 35 as of today. Locations of seven more units have already been announced, enough to double the number of stores by 1984. Sales have already doubled and so have profits, says Brooks.

The specific numbers are not made public because Lord & Taylor is part of the giant Associated Dry Goods Corp., which does not disclose sales, profits or other operating data for any of its chains. What Brooks says is that his division has "a very healthy, healthy, healthy bottom line."

Like most other upper-middle and high-end retailers, Lord & Taylor has prospered in the past year, despite a recession that has slowed the performance of many stores and particularly hurt mass merchants and discount department stores.

Fair Oaks is the fourth Lord & Taylor unit in the Washington area, reflecting a new strategy of saturating markets for maximum penetration rather than building isolated outposts, as many other big specialty merchants do.

Under Brooks the chain has bolstered is Chicago business by opening three more stores, invaded the Detroit suburbs with three units at once followed quickly by a fourth, then moved into West Palm Beach and put five more South Florida stores on the drawing board.

Succesfully expanding a group of large specialty stores requires more than just adding another identical link to the chain.

The Fair Oaks store, Brooks explained, carries about 60 percent of the same merchandise as the Chevy Chase store. The rest is selected for the local market. "We will carry just as many evening dresses here as at Chevy Chase, at just as high prices," he said. "But at Chevy Chase they will be more urbane. Here they will be more tailored, more suited to the country lifestyle. And Virginia has the most elegant country lifestyle anywhere."

Laid out like a two-story pinwheel, with departments spinning off from the escalators in segments of mirror, marble and muted carpet, the Fair Oaks Lord & Taylor has 100,000 square feet of selling space.