Steve left a comment yesterday that I'd like to respond to. I can answer his questions based on my research and personal experience. Yes. Alcohol abuse, as opposed to alcoholism, can and often does, cause someone to climb behind the wheel and drive under the influence. It's reasonable to speculate that a true alcoholic is much more adept and aware of their body chemistry. They aren't as likely to drive erratically for that reason, even though their blood alcohol level may be far over the legal limit.
In an alcoholic liver enzymes are working overtime. That's why tolerance to alcohol builds and certain alcoholics can drink others "under the table" and can "hold their liquor." Thus people who get caught for drunk driving are likely to be alcohol abusers, not alcoholics. Many people think that anyone who suffers problems due to drinking is by definition an alcoholic, but that isn't true.
An alcoholic is one whose drinking pattern has caused chronic, systemic physical and psychological damage, who must maintain a certain level of ethyl alcohol toxicity in their body chemistry or risk detoxification and its physical and psychological horrors (delerium tremens).
Yes, an alcoholic can be a binge drinker, too, but in true alcoholics I'll bet you'll find evidence of some maintenance use if you look hard enough.
So, this leads us to our next point. If a person isn't an alcoholic, what can they learn going to AA? Can they be "scared straight?" Possibly. For many, early intervention can create a climate of change which allows them to straighten out their lives. This is a good thing. AA permits this by asserting that its only requirement for membership is a desire to stop drinking.
It's a wide road. It's for those people on the fence unsure of whether or not they want to accept that they're alcoholics. Thus you don't have to make up your mind that you're an alcoholic before you walk through the door--you can decide later.
Also, you can remain in that state indefinitely. You never really ever have to admit you're an alcoholic, rather, you admit powerlessness over alcohol. It's semantics, but again, it's for those unable to deal with the stigma attached to the problem, or the idea that they'll never be able to drink again for the rest of their lives.
So to answer your question Steve, YES! An otherwise normal drinker, who has not "crossed the line" can indeed make stupid decisions while under the influence. They may be proto-alcoholics, or they may never go on to develop the disease no matter how much they drink. The AA big book references "potential alcoholics" being welcome in meetings. The problem this raises for "real alcoholics" is that it's much easier for these proto-alcoholics to stay dry.
My problem with AA is philosphical, and I have many, many points of contention. I don't have room to go into all of them here. But all in all, I want to state that although I have some personal animus with the way in which AA is practiced by individuals, and the way in which it is perceived by society, it ultimately does more good than harm. But it does do harm. And so, anyone who wishes to investigate AA should do so with eyes open. I recommend going to professional treatment first.