NavalEye
The word doesn't need to be airbrushed out of history - quite the reverse, because it is an example of how Gibson was a product of his age, class and upbringing.
But it does not need to be included in a modern film of the operation, because a repugnant controversy would distract a modern audience from the key elements of the film - the dedication and sacrifice of the crews.
And if you want to complain about the airbrushing of history, what about Mrs Gibson? It wouldn't surprise me if PJ included a girlie interest, but it will probably be Gibson's duty WAAF, not his troubled marriage.
So, when it comes down to it, what's the key moment; the sight of the Mohne Dam collapsing, with a third of the squadron down and more to go? Or the historically correct codeword being received at base?
Or Gibson going off to write the letters?