POWERFUL party elder Bo Yibo has grabbed the media limelight even as the health of his close friend, patriarch Deng Xiaoping, continues to draw intense speculation. A former vice-chairman of the now defunct Central Advisory Commission, Mr Bo last night appeared on national television and delivered ''an important speech'' on how to raise the efficiency of enterprises. The 85-year-old senior statesman and former vice-premier looked healthy. Mr Bo was invited to give a special address on economic efficiency at a national seminar chaired by Politburo member Li Tieying. Mr Bo's appearance last night was the latest in a series of public activities over the past fortnight. Last week, party authorities held a reception at the Great Hall of People to launch a new book by Mr Bo on recent party history. In his book, Mr Bo criticised the late Chairman Mao Zedong over the Cultural Revolution and warned against a ''dictatorial style'' of leadership. While considered close to Mr Deng, Mr Bo, the head of the so-called Shanxi Faction of the party, was also acceptable to the relatively large number of still active conservative elders. Analysts said if anything were to happen to Mr Deng, Mr Bo could form a ''bridge'' between the reformist proteges of the patriarch and the conservative wing of the party.