DALLAS — More than 400 lovers of classic knits motored downtown to the Fairmont Hotel this winter where Neiman Marcus hosted a luncheon and St. John fashion show with an appearance by designer Marie Gray to benefit the Gladney Center adoption agency. “St. John is our number one apparel business as of today,” revealed Ron Frasch, senior vice president and general merchandise manager. “The rate of growth in this business since August 1 is absolutely amazing. The only way we’re able to grow it is by attracting new customers and adding younger customers.” Sportswear and eveningwear are leading the expansion. Gray said her strategy is to think like the executive women who wear her clothes. “We try to approach it from the standpoint of the woman of the Nineties — What is her lifestyle? What does she need? What will work for her? — and then try to make the clothes exciting, but to fit that particular range of women,” she explained. Lately, customers have shown more interest in separates to add on to other pieces already in their wardrobes, Gray noted. The benefit, attended by seven members of Neiman’s executive management, raised $20,000 to establish the Dorothy B. Herkimer Memorial Fund for career development of birth mothers who live at the Gladney Center.