Just a thought, but regarding the number of crew needed to strike in order for 'significant' disruption to services, has anyone considered that unless there are enough defib trained crew on each flight then the planes won't be going anywhere? It doesn't matter if all the JNR and SNR's in the whole company turn up, if there aren't enough CSS's, FSM's and SEP/Av Med instructors to cover each flight then there could be a lot more cancellations.