[fastneutron]

> It's difficult to describe what this stuff is like if you haven't seen it.

I want to echo this point, because it gets talked about in the popular media like it's just another kind of garden variety crude oil, when it is anything but. For the curious, there are independent sellers (on ebay and elsewhere) who sell specimens of the stuff, along with samples of other kinds of raw fossil fuel and energy minerals. It's very helpful for demos and discussions like this one.

This stuff is almost literally road tar mixed with sand, almost like asphalt. It's difficult to break up by hand when cold, and when warm it has a tarry, putty-like texture. Contrast this with light-sweet crude, which is a pale yellow, gasoline-smelling liquid. Once you have a feel for these things, it doesn't take a leap of the imagination to grasp that the latter is going to take a lot less effort and energy to turn into useful products than the former!

[Solvency]

I wouldn't call any oil sweet but you do you.

[hackily]

I think you were unaware, but light sweet crude is a term referring to a type of crude oil. https://en.wikipedia.org/wiki/Sweet_crude_oil

[fastneutron]

"Sweet" means low sulfur. It's a standard industry term.