All baking recipes should be in mass for the dry ingredients and volume for the wet ingredients, definitely NOT weight. Because measuring flour by grams (mass) makes sense, but measuring flour by pounds (weight) is fucking stupid. Lots of people in this thread pretending to be smart by using SI units, but were apparently asleep in class when the teacher covered the difference between weight and mass. If you’re going to get picky about such a trifling difference between a volume of sugar and a certain mass of sugar at least get the details correct.
Hedwig sings a song about this myth, Origin of Love.