Ser vs. estar usage that is different from my textbook

[Joe Strider]

Whenever I think about the usages of estar, i like to break it down into three categories: feeling/condition, location, and gerund. In reference to the first, we use estar to talk about things that are true at a given point, but not an inherent quality of the noun. Since adjectives like hermoso and delicioso usually describe inherent qualities of nouns, it wouldn't usually be appropriate to use estar. As Rusty said, the only exception would be if you are describing something that breaks the norm of what you expect.