Some of the agreements can cause problems during disruption. I have heard of a flight a few months ago that was heavily delayed. The crew would have been in hours to do it if they had reduced their turnaround at LHR by 15 mins from the Industrially agreed level of an hour and whatever it was. They didn't so the flight was cancelled.
That to me is appaling when for the sake of the crew reducing turnaround at LHR by 15 mins (They would have still had over an hour) a flight got cancelled and a hundred or so pax had to be put in hotels. How much did they cost BA??!?!?!?
And what is the big issue against performance management??
I can see big changes coming and there will probably be a fight a long the way, although this time I don't think BA will give in!!