I must misunderstand
A polite way to say someone is an idiot and you’re not going to let them know.
I must misunderstand. You said the plan was perfect. It’s a mess, and no one knows what they’re doing.
I must misunderstand. You think I’m supposed to be excited about this? I’ve been stuck in a meeting for two hours.
I must misunderstand. You said the cake was good. I’ve been eating it since 10 a. m.
xs