What are the implications of art.11 of the European Convention on Human Rights: the right to freedom of assembly and association?

Article 11 of the Convention reads: "Everyone has the right to freedom of peaceful assembly and to freedom of association with others, including the right to form and to join trade unions." The right of a worker to be, or refuse to be, a member of a trade union, and the concomitant right not to be discriminated against, disciplined, dismissed or selected for redundancy for exercising that right (or for participating "at an appropriate time" in the activities of an independent trade union) has long since been imported into UK domestic legislation.