One of the problems I see is the limitations of the size of sail-driven ships and the mass of their cargo. Engine driven ships can grow to an arbitrary size with a large enough engine. Sail-driven ships are dependent on an area cross section of the sail (L^2), whereas their resistance scales with mass (L^3). They are also limited by the size of the sail beams you can build to hold all that force. Eventually you'd reach a point where your ship was all mast and no hull/cargo.

With steel, we may be able to build larger ships than in the age of sail, but would they be as large as modern cargo ships and oil haulers? (hundreds of meters long, hundreds of thousands of tons in weight?) My intuition says no. (Of course it could be wrong. I'd have to do some calculations).

PS
http://en.wikipedia.org/wiki/Supertanker

This is microscopic compared to the ships moving modern quantities of goods.

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Actually, resistance (or drag) does scale with length^2 (think either cross section or surface in contact with water), while tonnage scales with length^3, which is exactly the reason why ships grow so big, they use less fuel per ton-mile.

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And the "driving on the freeway on a scooter" analogy still holds true because the pilots are sitting in 7 to 30 ton aircraft o' doom and you are running around them in your very own Meatbody, Mark I. Beep, beep.
Trying to make sense of computers, The Error Log.

Some varieties of crude oil contain enough light fractions to be as thin and free flowing as kerosene. That may be what the Japanese were using as fuel late in the war, after American bombers had busted up their refineries.

And then there is these high sulfur crudes that look like something you would squeeze out of a grease gun. Not something I would want in an engine.

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With parachute sails--one might harness winds which do blow faster at higher levels.