KarlMarx, quite simply what option did BA have? Cancel or sub. What is the lesser of two evils? What else do you want them to do? And where did I say it was the passengers issue? Sometimes shit happens, and it is how the airline reacts that matters.
In this case compensation is clearly in order, so a dispute over compensation fair enough, but the sub itself, yeah have a whine due to the inconvenience, but lets get real the options were cancel or sub.