The example assumes that all other factors (like demand) remain constant. You are correct in saying that a higher oil price will lead some users to switch to a

The example assumes that all other factors (like demand) remain constant. You are correct in saying that a higher oil price will lead some users to switch to a different energy source in some scenarios. The point is to explain why financial commentators say (especially recently) that "the strong US dollar is causing commodities to sell off."