my favorite food is my grandma's apple pie, but I only think about it maybe twice a year. That comparison in the book was pitiful. All of the previous comparisons (done by RJ) made it seem like it wasn't worth living after losing the ability to channel, and that made Setalle an incredibly strong person for surviving without it. Now it's just not being able to eat your favorite food. She could have told Mat it would be like losing Tuon, or the ability to hear, or the ability to taste anything at all. The last would have been much closer than "you can't eat your one favoritest food"