What is more important- the vineyard or the winemaker?

Every couple of weeks, a fascinating topic surfaces on the West Coast Wine Network (WCWN) message boards. The WCWN is an active community for wine enthusiasts including posts from several respected winemakers (Mike Officer of Carlisle, Adam Lee of Siduri and Novy Family Wines, Brian Loring of Loring Wine Company, and Tom Leaf of Grapeleaf Cellars), esteemed grape growers (like Casey Hartlip from Eaglepoint Ranch and Wes Hagen from Clos Pepe Vineyard), and renowned wine scholars (like Carole Meredith, professor at University of California: Davis Department of Enology).

Earlier this week, someone posted a question: What contributes the most to a wine's quality- what is done in the vineyard or what the winery does with the grapes? Here are some highlights:

Role of Grape grower and Winemaker

• "...there really is no way to separate [integration of growing and winemaking-sic]. They exist on a synergistic continuum.
  ...over the last 20 years, quality improvements have been primarily spurred by a feedback loop between winemakers and growers. Hard work and experiments in the winery have informed growers about which clonal material works best at different site. Hard work and experiments in the vineyard have provided winemakers with options in the winery. Communication between the two has resulted in a profound improvement in fruit quality/wine quality.
  ...the biggest change in my winemaking has resulted from spending more time in the vineyards and selecting grapes based on the willingness of the grower to enter into a ‘partnership’ oriented toward quality. If the grower can’t recognize the difference between a good wine and a great wine, it’s unlikely that they will be willing to make the painful decisions necessary to grow great fruit (optimizing yield/more labor inputs). (Tom Leaf from Grapeleaf Cellars)
• "...when the grapes are perfect, the winemaker who stands back and lets them do their magic is the king. When the vintage is not perfect, then it is time for the winemaker to roll up the sleeves and get to work. (Scott from Windrow Vineyards)
• "To quote one of my mentors Richard Arrowood 'Get great grapes and don't screw them up'". (Jeff Gaffner from Saxon Brown Wines)
• ...it depends on the vintage year... In a great year, I...stand back and get out of the way...you're just the custodian making sure the grapes, must and fermented juice are treated as gently and as little as possible. However, don't forget the influence of the grower here, even in a great year, in limiting yields, leaf-pulling, pruning, pest control... Perhaps the grower contributes the most here. He/she always have major input in the final wine; they supply me with raw material that they've molded to their ideals and specifications... when there's a problem or two and the year is difficult, that's where I earn my keep. If I can make a damn good wine (although perhaps not great) in a poor year, I've earned my pay.
  ...[Winemaking] choices may ...be different for grapes from the same vineyard in different vintage years. And perhaps there's a stylistic synthesis of all the above factors to shape the final wine to what the winemaker envisions it. Winemaking IS an art form, albeit one requiring plenty of dull work along with the creative side.(Milan from Thunder Mountain)
• If one depends on purchased grapes then it is incumbent on that winemaker (as several of my colleagues have described here) to work in conjunction with the grower to try to get everybody on the same page. The success of the grower and of the winemaker are interdependent. This is the part of the equation that isn't so obvious in the abstract either/or question about vineyard vs. winemaker. For the winemaker without vineyards of his/her own, it's a good idea to find an area where the grape variety that winemaker wants to work with will do well, then find someone who's A.) already growing it or, B.) willing to plant it, and then to work with that grower to develop the highest quality fruit, by farming it with that focus in mind. (Steve Edmunds from Edmunds St. John)

Same Vineyard + Different Winemakers= Unique Wines

• "If you’ve ever had the opportunity to taste 5 or 6 wines made from basically identical fruit, you can’t dismiss winemaking from the equation. The differences can be profound. And not just in the ‘don’t screw it up’ sense. Style matters. All 6 wines can be equally ‘sound’, i.e., not screwed up, but you’ll obviously have strong preferences based on winemaking style. It’s amazing how a ‘house style’ can trump differences between vineyards at some wineries." (Tom Leaf from Grapeleaf Cellars)
• When... tastings of wines from the same vineyard and vintage by different winemakers; it has been amazing how different the wines are. The winemaker can have a great influence over the final product. The gift is knowing the difference between what you could do and what you should do. (Greg Harter)

Amount of Influence

• "I recently heard Merry Edwards talk about her winemaking and she went with the 70/30 split between vineyard/winemaking and I’d have to agree with her. Of course, it really is hard to tell where one starts and the other stops and drawing the line is pretty arbitrary." (Tom Leaf from Grapeleaf Cellars)
• 75% Vineyard, 25% Winemaker- with 50% of the time in the vineyard. (Jeff Gaffner from Saxon Brown Wines)
• World class wines come from world class vineyards so I'd say it's 95% vineyard, 5% winery/winemaker. The amazing thing is what nature does, not what winemakers do. Of course I have to qualify this by saying this assumes the winemaker doesn't do anything stupid (it's such a shame when that happens). I guess if something stupid happens then you're not talking about world class wine anymore, just a missed opportunity...For less than world class fruit, the winemaker's role in creating a palatable wine increases. As far as a percentage I'd be totally guessing. (Steve Lagier from Lagier Meredith)

For the all the response's, check out the post on WCWN.