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Preheat the oven to 350°F. Lightly grease (or line with parchment) two baking sheets, light-colored preferred.
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Beat together the butter, shortening, sugars, vanilla, cinnamon, nutmeg, salt, and vinegar until fairly smooth; a few tiny bits of butter may still show.
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Beat in the egg, again beating until smooth.
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Add the baking soda and flour, beating until well incorporated.
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Add the oats (and raisins), stirring to combine.
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Drop the dough in 1 1/4" balls onto the prepared baking sheets; a tablespoon cookie scoop works well here. If you're measuring, this is about 2 level tablespoons (using a tablespoon measure, not a dinner spoon). For round, symmetrical cookies, be sure to leave 2" between them on all sides; otherwise, they'll spread into each other.
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Bake the oatmeal cookies for 12 to 14 minutes, reversing the pans halfway through (top rack to bottom, bottom to top). For softer cookies, bake the lesser amount of time; for crunchier, the longer amount. At 12 minutes, especially if you're baking on a dark pan without parchment, a few of the cookies on the edge should just barely have a bit of a pale brown around their edges. At 14 minutes, they should be starting to color all over.
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Sprinkle a bit of salt atop the just-baked oatmeal cookies to bring their flavor over the top, if desired.
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Remove the oatmeal cookies from the oven, and let them cool right on the pan.
