NY -- Standard&Poor's CreditWire 2/23/98 -- Standard&Poor's today placed its double-'B'-plus corporate credit and bank loan ratings, and its double-'B'-minus subordinated debt rating of Office Depot, Inc. on CreditWatch with positive implications. The CreditWatch listings reflect the company's improved operating performance in the second half of 1997, which exceeded Standard&Poor's expectations following the failed merger negotiations with Staples. Financial measures at Office Depot have been approaching investment grade for some time. Still, Standard&Poor's has been concerned by the short operating history of the office products superstore industry and the possibility that the company's competitive position was weakened by the failed merger. During the 10-month period of merger negotiations, which ended in July