What is so good about home brewing/wine-making these days, is the quality of the yeast, and this, coupled with decent ingredients on the market, you can make a pretty good white wine for a fraction of the price of a supermarket brand!
I do actually listen to my doctor, well, I have to with one arm forced behind my back, a gag made from starched hessian and the threat of a needle about the size of a petrol pump, and if she says cut down, I do!
So under those circumstances, quality takes over from quantity, and anyway, the days of getting a gallon down after a rugby game are long gone, although after the World Cup, it might have been a good idea again...