an arbitration clause, ther s Workers of Am., 422 F.2d 77, 81 (2d Cir.1970) (relying on “positive assurance” rule to conclude that employer claims were subject to arbitration). Notably, less than a month before this court heard oral arguments in this case, the Second Circuit again emphasized that although traditional rules of contract interpretation generally apply to these types of cases, they are not always “readily [ ] transposed into the context of national labor law—as though the notion ‘one size fits all’ applies in the law. On the contrary, in labor law there are other policies to con sider, in particular the strong presumption in favor of arbitrability....” Mulvaney Mechanical, Inc. v. Sheet Metal Workers Int'l Ass’n, 288 F.3d 491, 2000 WL 33730559, at *1 (2d Cir. Apr.24, 2002) (<HOLDING>). C. Interpretation of “Article XXIII:
holding that in the grievance representation context an employee must prove that the unions acts tainted the grievance procedure such that the outcome was more than likely affected by the unions breach internal citation and quotation omitted holding that presumption of arbitrability precluded employer from unilaterally repudiating its cba despite unions breach of nostrike clause holding that a cause of action for breach of a purported implied contract would require interpretation of a cba and the totality of the parties contractual relationship holding that proof of unions breach of duty to fairly represent is an essential element of employees hybrid suit holding that no modification of the original employment contract occurred when the employer unilaterally issued a new handbook