Was not the reason that the union had no input to the new crewing levels that they weren't talking to BA? I've heard numerous complaints about the new working positions on the jumbo too, and this is an area where the union could have a meaningful input, but if they are too busy saying 'no' then ultimately BA will impose in a less than ideal fashion.
On the matter of the matrix, I was flying Airbusses long before text messages were invented, so contrary to Jetsets assertion that it's all mates of pilots taking the club numbers over, it wasn't. Typically it was an evening flight ex BRU, GVA, ZRH, LIN with businessmen coming home early. I don't think anyone is realistically expecting you to feed 20 extra pax, but I've seen refusal to accommodate even one, even with catering available, and I've seen it many times. Another militant nasty is demanding 18 hours of when just a handful of minutes past the 'long day' trigger. That's not triggered by ops, I know this as I spent an hour with the purser as she tried to sort it out with them! It's these incessant spanners in the works which can exasperate other BA staff.
By the way, did you know the fish is Escolar and is banned in many countries due to the violent reactions some people have to it? Given that the pilots do fixed links at LHR and the crew meal may be the only meal for 8 hours, what do you think delaying to change to a non-poisonous fish might be prudent?