> I'm half convinced that wine connoisseurs are fooling themselves when they claim that they can tell the difference between cheap and expensive wines. TL;DR Y

> I'm half convinced that wine connoisseurs are fooling themselves when they claim that they can tell the difference between cheap and expensive wines. TL;DR Yes, it seems you're right about that. This has been put to the test many times, usually with comical results. This page[0] has some stories, e.g. : French researcher Frédéric Brochet "submitted a mid-range Bordeaux in two different bottles, one labeled as a cheap table wine, the other bearing a grand cru etiquette." Tasters described the supposed grand cru as "woody, complex, and round" and the supposed cheap wine as "short, light, and faulty." ...when Brochet served a white wine he received all the usual descriptions: "fresh, dry, honeyed, lively." Later he served the same wine dyed red and received the usual red terms: "intense, spicy, supple, deep." ...little correlation has been found between price and preference, even among wine experts, in tasting settings in which labels and prices have been concealed. Robert Hodgson, a California vintner...noticed that the results of wine competitions were surprisingly inconsistent. ...[he] approached the organizers of the California State Fair wine competition in 2005 with a proposal. In the course of their routine duties, he would sometimes present the judges with samples from the same bottle three times without their knowledge. The judges were among the top experts in the American wine industry: winemakers, sommeliers, critics and buyers as well as wine consultants and academics. The results were "disturbing"... "Over the years he has shown again and again that even trained, professional palates are terrible at judging wine." ...Hodgson continued to analyze the results of wine competitions across the state and found that the medals awarded for wine excellence "were distributed at random". [0] https://en.wikipedia.org/wiki/Blind_wine_tasting https://en.wikipedia.org/wiki/Blind_wine_tasting