The Chron article suggested that one should tip on the value of the bottle. Would that be the retail value or the restaurant value? Either way, that would make for one large tip if a 1982 Lafite were brought in. Retail at $1000, on lists for $2000, the suggestion is that the patron should tip about $150 to $300 for the wine. I think that is excessive. However, I do make it a point to give the wine steward at least $20 (on top of the corkage) for having to open and decant a bottle. And, I always share. I also up the general percentage of the tip (maybe by 5% if service is good ) to take into account that I brought my own wine, but I certainly don't tip 15% - 20% of the value. Am I too cheap?
by the way, i do agree with those who say that the corkage policy is being abused by those who bring in supermarket wines to save a buck or two. On the other hand, restaurants that don't provide fair selections on their wine list aren't doing themselves any favors.
And, while I am here, let me say that REDD has a very good and very fair wine list, offering some very reasonable selections like the Roederer Estate for $36, the Talley Chardonnay for $43, and the Egly Ourient for $107. I do wish they would relax their policy of limiting a table to two bottles corkage, even when a bottle is bought for each bottle. Makes it hard to share some really great wines in a larger party.