A friend explained this to me – it makes everything a lot clearer. Justice Griffith found that the BC Liberals had torn up a legally-binding, negotiated contract (that contained class size and composition language) and that they had bargained in bad faith. Because the Liberals appealed the decision, they have avoided re-instating class size and composition language into the contract under negotiation.
If the Liberals legislate teachers back to work, they will confirm to the courts that they are once again unable to negotiate a contract with teachers. The Griffin ruling will therefore remain as the most ‘current’ language in the contract.
If the BCTF “accepts” the current offer on the table (that does not include class size and composition language), it would trump the Griffin ruling and any hopes of re-establishing classroom size and composition to past levels. Why would the BCTF accept anything less than what the courts have told them is legally theirs?