Imbibing: What is Considered Moderate?

Many readers have probably already seen this recent study from Australia [h/t to Jack]:

Moderate drinkers make better thinkers than those who tipple too much or not at all, a new Australian study says.

Verbal skills, memory and speed of thought were all faster and better in people who drank moderately compared to heavy drinkers and teetotallers, according to tests done on 7 000 Australians.

So, the production of mental output as a function of alcohol is quadratic with a negative second derivative, reaching a maximum at a "moderate" level of drinking. Okay, but what is considered moderate? At what quantity is the marginal physical product of alcohol equal to zero?

Men who consume 14-28 alcoholic drinks a week and women who imbibe 7-14 glasses a week were classed as moderate drinkers.

Two to four drinks per day is moderate?????

As Jack said, "Remember, the study was carried out in Australia."

I have quite a bit drinking to do, just to get up to that level! But I know it's good for me, so I'll make the sacrifice.