You know the procedure by now. The wine was an aged cru bourgeois Bordeaux, which I chose in response to this tasting note:

Initially, the wonderful black fruit is completely dominated by oak, tannin, and acidity. It takes at least an hour in the decanter for the black fruit to start showing.

The decanted wine was aged for 3 hours. Everyone did very well:

Everybody correctly identified the odd wine out. Housten and Sally also correctly identified the source, although for opposite reasons. Sally chose 2 as the decanter because it had less aroma, Housten choice 1 as the bottle because it had not opened up as much.

I, it seems, agree with the tasting note that the decanted wine is fruitier. This doesn’t support my hypothesis that decanting the wine depletes the aroma, unless you invoke the masking theory proposed in this post.

[Added after posting] Amy’s note, however, agrees with the hypothesis, although she misidentified the source.