Oh, really. And who decides what ideas are stupid?
If a cake recipe calls for 1 cup of sugar and you don't have sugar so you add one cup of salt, would you think that's stupid? Salt is the opposite of sugar, so it would be stupid. You might think the salty cake is good, but you didn't make it as it was intended and it probably tastes like shite.
It's the same with the peanut butter chile. The guy's recipe called for chocolate, which would add a bitter-sweet taste. He had no chocolate so he added peanut butter, an umami-salty taste. it's the opposite of bittersweet chocolate. He created the opposite flavor of what was intended by adding the chocolate. There is a reason the chile recipe calls for chocolate, just like there's a reason the cake recipe calls for sugar; it adds a certain layer of flavor that compliments the other flavors.
So yes, picking the exact opposite flavor of what is called for in a recipe is stupid. You don't substitute one cup of salt for one cup of sugar.