I used to work as a chef. I'm healthy weight, exercise well, know how to cook. I love dim sims and once every two years get a craving for tinned tomato soup.
I know how to brew beer, am personally familiar with almost every style of beer available in this country commercially and a few HB versions of styles that are less available. I have conducted and participated in taint sessions and am BJCP certified.
At the moment I am enjoying premixed bourbon and coke and ice cold barvaria longnecks.
Knowing what is good and what is crap doesn't occasionally stop you getting a hankering for crap. People watch **** TV, read **** books, newspapers and magazines, eat **** food, drink **** beer. As long as you don't make it your life or remain ignorant of the world out there, I don't think it's always a bad thing. See it as a challenege, brew something in the ballpark for your brother. Then teach him how to make it.
Summarised as recognising a turd doesn't stop you from sometimes wanting to eat one. You don't even need to polish it. I think not recognising it is the ultimate sin.