In reply to:

Funny how you can just know when someone has never walked behind a horse drawn plough

Not only am I a full-blooded Merkin but a city boy, to boot. If memory serves, most of the time I have heard the unit furlongs per fortnight used it has been used in reference to the speed of light. There are large pockets of horse drawn plows(sic) not far from where I live these days.