Totally agree with Ark. Airlines do not shrug these sort of things off. In a similar situation you would be fired instantly (BALPA pleading your case or not!). As an aside, in commercial operations fuel is always tight cos it is 'bad' to carry around non-profit making loads and every pound saved could go towards another fare-paying bum on a seat, etc, etc. It is routine to land with what approximates to MLA - yes I know that is to a fixed airfield but there are often 'events' that can errode the fuel remaining!
Perhaps it would be refreshing to see some heads roll on this one? Perhaps it would drive home the reallity of ditching a multi-million pound aircraft at a time when defence can't afford a new box of paperclips? Perhaps it keeps happening because there is an unspoken 'you can't make an omlette without breaking a few eggs' mentality - the proper conduct of embarked aviation gets lost in the noise and excitement of the exercise. Flying is never 'for exercise'!!