Ever walk into a retailer and have them extoll tales of the double secret declassified grapes that Cult Napa producer basically gave away? It's one of the most cliched scenarios, retailers make bank off this idea, and the reality is, you're getting duped. It's not necessarily the retailer that's doing the duping though. It could be the producer, it could be the distributor. No matter, the truth is, you just cant get Screaming Eagle for $30.
There are 2 ways for the winery to get grapes, they can grow it or they can buy it. Most of the great wines are vineyard specific, or at least a small collection of vineyards specific. None of the top producers use all of their grapes. Not because there's not a market or because they need cash, but because the grapes simply don't make the cut. No matter how good a vineyard may be, there will always be some sub par grapes. Rather than throw these away, they are often sold off on the open market, sometimes as grapes, sometimes as juice, sometimes as finished wine. Typically, there's not enough of any one of these producers left to do anything substantial, production wise, so they need to be blended with other sources. This is the great secondary market, and it produces some very solid wines. For a $20 Napa Cab, or a $15 Monterey Chardonnay it's worth every penny.
Once in a great great while, an esteemed producer will declassify their grapes because their harvest was inferior. They will either put these into one of their own proprietary wines, or sell these off to a separate label. It's these wines that are rumored to be "whisper whisper whisper, Napa Cab" that usually sells for $100. It actually doesn't really matter if it is. This isn't TJ Maxx, the wines are getting discounted because the label is ripped, or last year's item. They are discounted because they are inferior. That means they're not up to their standard, so no, it's not Screaming Eagle. Your harvest is everything, when it sucks, it sucks. You just can't fix it. I'm not saying the wines are undrinkable. Maybe, in the right hands, the wines can be quite good. Then you throw in the rumor/ hype factor. By the time the information gets to you, how accurate is the story? The bottom line is, you get what you pay for most of the time. Don't get super excited that a retailer tells you about the amazing deal they scored by a declassified something or other. Just remember it got declassified for a reason.