There I go with those pesky ‘facts’ again. ;-)
And if you ever post any facts, I'll tell you.
I finally checked out the source you posted. The source is a question-and-answer board from 2012, and the quoted "science" is from a DEA judge in 1988.
a. This is hardly a scientific source.
b. They really do quote ".9 grams". Other sources go as high as 1.2 grams for a cigarette, so at least this number is in the ballpark.
c. So, using the .9 gram base makes the death dose median 59.4 pounds as I calculated above. Not 1500 pounds.
d. According to one source, THC content of marijuana has increased 2.5 times from 1988 to 2009. Based on your source lethality factor (which I don't accept, by the way), this recalculates the death dose median as 23.8 pounds.
e. And finally, 79 potheads posted hi-larious Cheech-n-Chong style idiocy on your 2012 source, and not one of them mentioned the faulty math.