How's Your Nose?

Can you tell the difference between a cabernet and a merlot, without drinking either one? Are the differences discernable by only your nose?
On a recent wine-tasting tour of Napa Valley, it was difficult to determine the subtleties after we downed the approximately three bottles of everything that was offered over the preceding hours.
Not surprised? Me neither. We had plenty of whites, reds, syrah, etc. and by the end of the day, it was all I could do to maintain an air of pseudo-sophistication. Indulged? Yes. Hammered? No.
We truly enjoyed Coppola, Peju, Mondavi, Cakebread, and all the other well-known wineries which charge $12-25 for a tasting. This amount is, of course, applied to any purchase made on the spot. We also really enjoyed the smaller, lesser-known wineries that felt friendlier and seemed as if they actually wanted us there. Sometimes, it is more fun to stumble upon a winery than to be directed to one by reputation.
Take a drive up 12 and discover everything there. The Wine Train is not recommended by many, however, a designated driver is. The roses and mustard are great local crops in addition to grapes. Who knows? You might return home pining for some Two Buck Chuck, which continues to be highly rated in blind taste tests across the region.
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