What is cold stabilisation?

I have heard winemakers claim their wines were ‘cold stabilised’. What does this mean, and does it improve the wine?

Cold stabilisation is a process designed to prevent the formation of tartaric acid crystals in the bottle. The wine is kept at –4 degrees for about a week. The tartaric acid crystals form and drop to the bottom of the chilled tank, leaving the wine clear. Some winemakers believe this removes some of the flavour from the wine, but most buyers of commercially-made wines don’t want to see sediment at the bottom of their glass after drinking the wine. Before the discovery of cold fermentation, red wines were routinely decanted before serving, in order to remove the sediment. Modern wines seldom need decanting, especially if they have been cold stabilised.