The link you provided does not say what you say it does.
Further, I find it hard to believe that the placebo effect is stronger than the well-documented effects of alcohol in impairing judgment, impairing the frontal lobe and motor skills, creating long-term changes to the reward circuits in the brain, and by lowering inhibitions on all forms of ill-advised behavior, which includes aggressive behavior.
I was originally looking to link to something less like a lab report, but you can see the original studies here, and in the references associated.
Basically, the more impaired you expect to be, the more impaired you become. So, if you expect alcohol to make you violent then you will behave more violently under the influence. Of course, one would question why, if you expect alcohol to make you violent, you would drink at all - other than to use it as an excuse to behave like a dick.
Alcohol will affect your reaction time and your motor co-ordination. It makes you feel awful the next day as the liver is taxed by removing the poisons from your system. It's an addictive substance and is associated with a myriad of substance abuse problems.
Whilst it is true that alcohol will have an effect on your body chemistry, it does not make you violent, it does not make you behave badly or aggressively. Those behaviours come from within you. Alcohol is not an excuse for behaving like a dick; it may, however, be something that you accept as an excuse for letting out the dickish behaviour you wish to display.
I don't know of any scientific studies that show that alcohol lowers inhibitions, but the above studies (and the references in their bibliographies) show that people will lower their inhibitions when they think they are consuming alcohol, regardless of the alcohol content of the drink.
You're right that alcohol doesn't transform a normal person into an aggressive person, but it does lower inhibitions to otherwise anti-social or ill-advised behavior.
Further, I find it hard to believe that the placebo effect is stronger than the well-documented effects of alcohol in impairing judgment, impairing the frontal lobe and motor skills, creating long-term changes to the reward circuits in the brain, and by lowering inhibitions on all forms of ill-advised behavior, which includes aggressive behavior.