It's not just weight that's variable, it's flavor too! I cook all of my family's meals, and when I started out years ago, I tried to write down recipes exactly

It's not just weight that's variable, it's flavor too! I cook all of my family's meals, and when I started out years ago, I tried to write down recipes exactly, weigh everything (how much is a cup of flour when density varies?), but then I realized, all the damn ingredients aren't the same twice. Carrots can go from bitter to sweet, potatoes can range from starchy to gooey, herbs can be really subtle, or really strong, it depends on the weather. Even in my own garden, the herbs are completely variable. The only thing that seems consistent is meats and inorganic things like salt. Corn fed beef is different from grass fed beef, for example, but within each category, pretty consistent. So, frustrating as it is, it's near impossible to write a perfectly reproducible recipe.