I don't know about David, but one of the very first things I learned in college was how much a "kilo" weighed. Even Arlo Guthrie, son of the all american folk singer woodie sang about
[quote]Coming into Los Angeles, bringing in a couple of "ki's", don't touch my bags if you please, Mister Customs Man[/quote]
Back in the 60's all the good hashish came from London so you had to learn the metric system. One Stone was not used for weights in the counterculture since it involved too much math and decimals (example one stone would be 6.35029 kg) instead it was a measure of consumption,
Ah, my misspent youth - glorious
charm