It means the replier understands it.
Now you can get a SERIOUS reply to a tongue-in-cheek question...that's okey dokey.
A tongue-in-cheek reply to a serious question....that's okey dokey too but well less so unless it is snarky sarcastic arrogant impudent smart alecky and condescending. Them I don't like whatsoever.
What's YOUR cuppa tea prithee?
