So this is what I found regarding the English System of Measurement:
"Although a few of the English measures are still in use in Britain today, the country has officially moved to SI. Only the U.S. (which uses the US Customary System), Liberia and Burma have not officially adopted the SI standard."
From this, I'd say is safe to assume that the authors of the glider recipes are using the US Customary System, and as such try to use the American TBS and tsp. Because as Blue says, though it may not seem as much of a difference, in a glider's diet it can be huge.
There's been many talks about USA officially moving to SI, like Britain did. And though there's been some changes (for example I'm a engineer and since I started working I've never had to use English units), there's things like recipes and such that would be hard to change, and it can be very confusing for people of different background.
Sorry for the rambling. I had been following Blue's other posts that brought on this topic, and quite honestly I didn't even know that there were English and American TBS and tsp. And when I saw Candy's algebra I sort of said in my head: "Holy Cow! What is this witchcraft!". And for those that have watched Monty Python: "We found a witch! May we burn her?" No offense, Candy
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