Answer: One way to never display alcoholic symptoms is to never drink.
I believe Alcoholism is considered by the American Medical Association to be a chronic disease, like diabetes. Check their web page to see what they say about alcoholism.
People I know who have recovered using the Alcoholics Anonymous recovery program tell me that alcoholism to a three part disease; a) physical, b) mental/emotional, and c) spiritual.
Apparently, when an alcoholic drinks alcohol, it triggers an involuntary allergic reaction. For alcoholics, the reaction is an irresistible physical craving to drink more alcohol. That is why they keep on drinking beyond normal amounts of alcohol.
For more about this, you can read the book "Alcoholics Anonymous".
My recovered alcoholic friends tell me that if someone has to count how many drinks they are having (trying to prevent getting drunk, again) , has ever passed out, blacked out, driven drunk, repeatedly drank more than they wanted to, or has a distinct personality change when they drink then they might already be, or may be becoming an alcoholic.
On the other hand, the Jude Thaddeus Program (soberforever.net) appears to be the most effective approach to alcohol dependence and alcoholism in the world. It is a research project operated by the Baldwin Research Institute, a New York State not-for-profit organization owned by taxpayers.
Independently-conducted research has established an overall success rate of 63.5% for the Jude Thaddeus Program. This compares to a success rate in the range of 0-20% for conventional programs. Alcoholics Anonymous(AA) reports a success rate lower than 5%. Research also indicates that no treatment at all has a success rate of about 30%. This suggests that traditional programs are less effective than doing nothing.