To what extent have people shown the ability to consistently distinguish even that much in a blind test? I've certainly had good glasses of wine and bad glasses of wine, but I wouldn't want to swear that I've always been consistent about which vintages or even which bottles were in which set.
Even from bottle to bottle there can be variation in terms of how good the wine is. I've had occasions where I've opened up a bottle of wine, and it was off, clearly wasn't tasting right. I opened up a second bottle of the same wine, literally a bottle from the same case that had been stored next to the one that had gone off, and it tasted fine.
Why did the one bottle go bad when the one next to it was just fine? Who knows. Maybe the one bottle was contaminated with something, maybe the cork wasn't good, maybe that bottle was stored in a hot spot in the winery before making it into the case. But if all I had tasted was the bad bottle, I would have said that the wine was pretty unpleasant, and if all I had tasted was the good bottle, I would have said "yeah I'll buy a case of this".
BS. You can't tell the difference between expensive wine and cheap wine, but I bet some wine tastes significantly nicer to you than other wine. Wine that tastes good is good. It's just very subjective.