Occasional Beer & General Sin

Beloved Dhananjay,

Say I have a pastime that I share with my dad. I drink a beer every weekend, once a day, Saturday and Sunday. I limit myself to one and am fine with the limit that I've set for myself. According to your explanation of the Ayurvedic science, I know that loosing the seed is the most extreme way of losing vital energy. According to your past answers, I know that as long as I drink 2 beers per a weekend (or alcohol whatsoever), I will only reach a certain point in my gaining of samadhi and buddhi nadhi. I will reach a limit where I must turn from my sin. I still drink these beers because I enjoy a drink with my dad every weekend that I come home from college. I'm truly enjoying my progress in my path of Brahmacharya and enjoying this past time. It doesn't seem to hold me back because I am always seeing improvements in my focus/strength in daily life.

My questions are
1. How might these beers hold me back from peak performance in my sadhana/meditation?
2. Is the effect a lot or a little?
3. When and how will I understand when it is time to quit any particular sin? Especially limited alcohol intake? I know isn't just sexual immorality, negative emotions, and lack of Atman that we are to avoid.
4. When I do drink, I get a tingle at the same place on my head about halfway through a beer. Is this because my brain is affected? It sure seems like it.
5. Do you believe that I should stop all drinking henceforth? I can buy nonalcoholic beers, although I enjoy this appointment as it is. I see you as my guru, and I follow your advice to the fullest.