I've heard over and over that when it comes to baking, measurements cannot be ignored, and you need to be very precise. This question covers how precise a measurement of flour should be, for example. But if getting your baking just right requires being so painstaking in measuring ingredients, how is it possible that all of the amounts in recipes come out to such neat and easy numbers? I can't remember if I've ever seen a flour measurement go more specific than the nearest 1/4 cup. The smaller chemicals like baking powders are usually to the half tsp, that I've seen, but I can imagine they go down to 1/4 or 1/8. And eggs basically always come in ones, or one yolk, but there's not much you can do about that. Weight measurements are more specific of course, but have you ever seen a ratio like 4.2683 oz of flour per egg?
How accurate is this really? Does this mean if your flour measurement is off by 1/16th cup you'll be just fine? Or it just won't look the same as the one made by the person who invented the recipe? I have a hard time believing that with such complex chemistry involved, the optimal quantities are so close to large fractions of our units of measure. Is there actually a bit more fudge room with some ingredients than we're being told?
Also, if so, which ingredients are more forgiving? I'd guess that baking powders are among the least.