Last night we were served two rieslings by a young sommelier, who is a bit raw but talented. ( It's been fun to watch his learning process.) One of the rieslings was a Trefethen dry. I don't remember the vintage, but the nose was flatout petroleum or gasoline. The taste was lovely, although my husband says he found it slightly oily in the mouth. Is this a characteristic? I can't believe it isn't a flaw or that a jug of transmission fluid didn't fall into the barrel. The sommelier couldn't explain it and accepted the strangeness without question.