It is ultimately progressive. Some can function at a certain level for a period of time, but not forever. If nothing else, health over time will deteriorate. That could be liver dysfunction, high blood pressure, peripheral neuropathy, etc. Alcohol is a toxin to the body when consumed in abnormal quantities over a long period of time. There are those who feel the effects immediately, and those who take a few years.
No one "finds" a level of dysfunction that "sorta works" for them and stays there. To believe that is to believe that the A has some control over the disease. They do not, but that is part of their denial about the reality of the disease.