Holding that the remedy provided in §§ 515 and 502(g) "is limited to the collection of `promised contributions' and does not confer jurisdiction on district courts to determine whether an employer's unilateral decision to refuse to make post-contract contributions constitutes a violation of the NLRA."
Explaining that the deferential standard of review is appropriate because the "[the ALJ] ... sees the witnesses and hears them testify, while the Board and the reviewing court look only at cold records"
Holding that courts must not "substitute [their] judgment for those of the Board with respect to the issues that Congress intended the Board should resolve"
Finding no impasse where “little substantive bargaining had taken place” during the parties' few negotiation sessions and the union had made proposals that “obviously were grist for the collective bargaining mill”
Concluding that union's dismissal of employer's proposals as "ridiculous" or a "slap in the face" did not constitute conclusive evidence of impasse, recognizing that "exaggeration, posturing and dilatory tactics . . . might be expected in labor negotiations"