I've read the entire thread. I enjoy an occasional cold beer, especially when cooking on the barbecue or relaxing with friends at a social setting. One beer. I don't ever want to be impaired in any way. Life is challenging enough without all of my senses on highest alert.
Now comes to the bike riding... the answer is no. Not ever. Again, I think that the risks of riding are great enough without compounding them by taking away either my hearing, my judgment or my reaction times (all of which are influenced by alcohol). No.
The same goes for anything athletic. Heck, I'm 56 years old now, and cannot afford to give away anything more than I've already lost in terms of quickness, flexibility, balance. Also, beer is an ADH suppressor, so it's throwing off the body's water balance, leading potentially to dehydration. Again a performance limiter. So, no.
I hope that this isn't difficult to understand.