It's only crazy if you use shots or ounces. Five-sixths of a shot equals 25ml, the UK legal measuring unit for spirits and one of the most used measures in Europe, where bartenders work in increments of 5ml.
I’ve rated this the full 5+ stars! I love the difference the falernum brings when compared to triple sec in a margarita. Tempted to try this again soon but with anejo instead of reposado.