This is roughly the graph Krista was talking about towards the end of her post.
The effort to enter calories tapers off as all your common food is entered, and in time you'll hit a constant low rate of foods you haven't entered into the system coming up in your day to day eating.
Also, on a separate note, Krista just jumped up saying "I can just figure this out empirically!" as she ran off to get the kitchen scale. She's telling me the alternate ways to figure out how much a muffin weighs. You know what's tricky? Telling how much a muffin weighs when you have a whole bunch of muffins and a scale.
Also, says Krista: "The math was true!".