I'm thinking the dog turd comaprison is a bit off base.
I have plaster ceilings with a 1 x 8 T&G wall board underlayment (or would that be overlayment since it's above the plaster?)
Anyway, you can see the joints of the wall board in just about any light, natural or artificial. The joints aren't taped, so you don't see rises, you see smooth "indentions" under the 3/8" of plaster.
I don't mind it since I think it adds character, but it's been noticed by more than one person just sitting on the couch and glancing up.
"Hey, your ceiling is sort of wavy...what is that?"