re: Letting wine breathe... real or placebo?

Cooks Illustrated did blind taste tests and found that "Red wines—especially young, undeveloped ones—often benefit from a breathing period after opening so that oxygen can break down tannins and sulfur compounds, softening harsh flavors."

"But merely uncorking a bottle and letting it sit for a bit is insufficient. In order to truly aerate wine, as much of its surface area as possible must be exposed to oxygen."

They used the aerator devices, a 30 second run in the blender, or pouring it back and forth between pitchers 15 times.

"The results were remarkable: The undecanted wines were predictably astringent and flat; the wines that had been decanted by pouring were bright and balanced, their tannins less prominent, with more complex aromas coming to the fore. The blender-decanted wines tasted more developed than the undecanted ones but not nearly as developed as the wines that were repeatedly poured."

White wines did not benefit. "Most tasters found the aerated samples “less fruity” and “less acidic,” not to mention “dull,” “flat,” and “characterless.”"