Don't know how old you are but, I was born in the early 70's and it was pretty common slang around my region and most knew the reference. I don't know what we are doing for once, I was just giving some guidance on why someone of an older generation or of a certain ancestor could be offended by the comment. In all honesty I could not care less if he uses it, as it has pretty much fallen out of colloquialism and I am not the type to get offended, but the parent poster genuinely seemed unaware of what offence they did, so I offered one of many possible explanations. I get it, people are too sensitive now days and you have an axe to grid about it, fair enough, but I personally don't think I was doing anything other than providing a possible explanation.