The previous article showed that high quality closely depends on maintaining a certain balance or, at least, on a non-limitating level of the TLS/P ratio (total leaf surface to production). For obvious reasons, this level is more easily reached if the production per vine is limited. However, the main problem for the vine grower consists in knowing how to balance this ratio, and essentially, how to maintain it over time. One of the sacrosanct treatises of international viticulture (Winkler et al. 1974), certainly old but still relevant especially with regards to certain physiological principles, describes the rationales for winter pruning in the vineyards. The main reason is that “pruning prevents us from having to thin the clusters later on”. We absolutely share this point of view. The major reason why pruning eliminates 80 to 90% of the wood per year is the early regulation of the cluster load, which, otherwise, would almost certainly be too high. From this point of view, winter pruning clearly is a “common” element for the regulation of the cluster load in the vineyard. To access the full text of this article, follow the link on the right