I really don't like the way this thread is heading..... Something of the BNP about it, I regret to opine...
Honestly chaps, the only way ahead is to convince the mate who took such offence to view the whole thing in its historical context. Such as letting him know that although the Slobrador's name was considered an affectionate term for a loyal friend over half a century ago, nowadays the RAF wouldn't dream of countenancing such a thing...
Look towards the positive, don't just make silly points about a word which is completely unacceptable in present day usage.
Apart from which, I understand that Gibbo's dog was actually rather a pain in the ar$e for many at the time!