Robert Parker's wine buyers guide has a lot of information on which wines he likes and assumes you will like too. But after buying one of those wines, you are pretty much on your own as to how to serve and enjoy it maximally. E.g. Parker says"red wines can be served within 15-30 minutes of being opened...there are exceptions of wines which improve for 7-8 hours, but these are quite rare."
well in my experience they are not rare at all among the wines Parker is raving about in his book. e,g, after reading his rave about the 1996 ducru beaucaillou, i spent around a hundred dollars, and served it to friends who actually laughed at how terrible it was.
My error was in not letting it breathe for at LEAST 30 minutes, and better for an hour or more, or even a day. Many many red wines I have had since beginning to buy good ones, have tasted better the next day, and some even after a week, while the average good 10-15 year old wine seems to need 2-4 hours.
Michael Broadbent could have saved me this waste of good wine had I read his advice: "Red bordeaux of a sturdy vintage, say a 1996, or even one of the tougher 1990's, will be so full of tannin and extract that decanting in early after noon for drinking around 8:30pm will encourage it to relax and soften a little. How many times has one been told, and occasionally discovered accidentally, that a young red wine seems softer and better on the palate the next day? The same can be said of very old wine of finest quality, though it is only a brave or singularly curious person who will risk this.....My final advice on 'air' is: be bold, try decanting well in advance."
I am sure knowledgable wine drinkers know this, but it is not so easy to find in the popular sources I had been reading. I recommend Broadbent to all novices. Ten or fifteen dollars spent on this book would have saved me wasting over a hundred just on that one wine, and more on countless others before and since.