A few months ago, the London bartender Tony Conigliaro told me that weak cocktails can be more aromatic than stronger drinks. That observation provoked me to play with the proportions of alcohol and water in spirits and wines. Then this month, a barista showed me that I could make tastier coffee by brewing it with less ground coffee and more water. It’s true, as it turned out: Water is indeed a useful flavor enhancer, exactly because it dilutes other ingredients and can change their balance for the better.