In addition to the illegality of carrying fuel due to the Dangerous Goods section of the ANO, Genghis's post gives some interesting information regarding safety. I have no idea what kind of g-force the average plastic can can take, but I'd guess it's less than 9g.
So in addition to being illegal, carrying fuel in a can is probably far less safe than carrying fuel in your aircraft's tank.
I think that settles what was left of this argument! Interesting, nonetheless.
FFF
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