Most winemakers are practicing minimal intervention techniques these days, allow the vineyard to speak is the ethos and we can only agree.
Getting the fruit right is most of the battle won and this is why vintage variation occurs. If grape quality were not the paramount concern in the winemaking process then every vintage would be quite similar as all else in the process is under the control of the winemaker. Using our own fruit and purchasing from selected growers is the best way we can ensure the best possible fruit for or wines.
The biggest point of difference between us and the majority of the Barossa winemaking community is here at smallfry we rely on wild yeast to conduct the primary alcoholic ferment.
The ideal scenario came with the great 02 vintage where the first add of any kind came when we added 40 ppm of SO2 after malolactic ferment was complete. So no yeast, no HTA, no malo bugs, no DAP nada.
Our 04 was a bit out of balance so we did adjust the pH with 1 g/L of Tartaric Acid but again primary and malo ferments occurred spontaneously. 05 is the same story.
Why wild yeast? My belief is that the different flavour profile obtained using wild yeast ferments is primarily due to population dynamics. The ferments can take a day or so to get going, during this time preferment maceration of skins occurs extracting a more fruity flavour profile.
Most winemakers I know would add a cultivated yeast inoculum in a high population at the crusher or in the fermenter with the express intention of getting the ferment going as quickly as possible. This is not wrong, it is simply a different approach.
Another option for preferment maceration would be using cooling to chill grapes, before warming them again and initiating ferment.