The book contains many suggestions for cocktails. There is one for a mixture of stout and champagne. The book suggests that you if pour the drinks in VERY slowly you will get a glass with the liquid separated. You can see the results so far. I have never really liked champagne. Sometimes it gets served as part of the pre-dinner drinks part of a conference. I like the challenge of creating this super-cocktail of guiness and champagne. In my minds eye I see myself surrounded by cheering people as I finally create, what the Harvard book describes as a "black velvet". I will give a little bow and say "I have recreated a drink that beats the second law of thermodynamics. My next project is to create a drink that cheats death."
What is more likely to happen is that when I take a glass of champagne from a waiter and pull out a can of stout from my jacket, people will start whispering about "losing it". People will start edging away from me as I hold up a glass of murky black stuff, and start ranting about death and thermodynamics.
Still you can't live you life worrying about what other people think.