^^^^ Um, the math is easier if you DON'T convert to gallons. 20-liter pail of oil for $30 is $1.50 / liter, 5 cents a liter more than the diesel. So it's close.
Stateside, we're paying aprx. $4/gallon for diesel. The "pails" of oil here are 5-gallon, and even the cheapest oil is aprx. $40/pail, so about twice the price of fuel. So Canada is experiencing cheaper oil, and more expensive fuel, than we get.
So why does that article, after talking about getting rid of the throttle and spark plugs, show an animated diagram of an Otto-cycle engine?