Woofgang, if you look back to the first page of the thread, you'll see that Mamyalynne's contribution, timed at 1210, referred to her cringing at the use of the phrase "off of". My later offering was in answer to that.
If anyone wants a more recent illustration of the phrase than those I offered, they need only consider The Rolling Stones' exhortation: "Hey, you, get off of my cloud!"
Nowadays, it is probably more frequently heard as what amounts to a single word "offa" in instructions such as "Get offa that bike!" The 'a' is merely an abbreviation of 'of'.