I know this is old but I'm posting anyway. I don't know if this is how others in my generation interpreted the incorrect saying, but I personally always read it as a threat. It may or may not have been a serious threat or one said in jest but still a threat. It made dialouge seem either angrier or more flippant than the correct version did. So it looks like I have another think coming. Thank you for that tidbit. I have only recently come across the correct phrase in a series of books I'm reading, and I've heard the incorrect version (and believed it to be correct) for so long that the moment I read it, my mind would correct it, however because this phrase occasionaly appears in this series it has been conditioning my mind to think the correct version instead.