That's a true assessment as far as it goes, but, if you know how to combine gin and liqueur, you'll see that this truism just doesn't go far enough. Neither liqueur nor flavored brandy need be reserved just for desserts. Slings are sweet drinks made with brandy, whiskey, or gin. Here's the gin version. Cornell Cocktail Serve straight-up in a chilled cocktail glass.
Recipe makes two drinks.
Gin Sling Serve in an old-fashioned or lowball glass. Club soda to fill Fill serving glass half full with cracked ice. Add all ingredients except club soda. Add club soda to fill. If you don't want a fizzy drink, substitute plain water for the club soda.