No. 96-1309 Argued April 3, 1997 Decided June 20, 1997 C.V. Stelzenmuller, Birmingham, AL, argued the cause and filed the briefs for petitioner. Sharon I. Block, Attorney, National Labor Relations Board, Washington, DC, argued the cause for respondent, with whom Linda R. Sher, Associate General Counsel, Aileen A. Armstrong, Deputy Associate General Counsel, and Linda Dreeben, Supervisory Attorney, were on the brief. On Petition for Review and Cross-Application for Enforcement of an Order of the National