I just stumbled upon this, and figured I'd put my two cents in.
What if Superman makes a comment about something from growing up as a farm kid, something that is not common knowledge for people who aren't farmers.
For example: crop insurance will not cover full cost of a lost crop unless it had been planted by a deadline (in Indiana it is May 5). If something prevents planting or something happens to the crop before planting is completed, the insurance only covers half the value of what the crop would have sold for at harvest. As a farm kid, that deadline would've loomed large in Clark's mind growing up; but Superman shouldn't have any knowledge of it.
I have a scene that randomly popped into my brain.
where Superman goes to Lois upset after trying to help a farm community from a disaster that severely damaged fields and preventing planting to be finished by the deadline.
Lois tries to reassure him that the farmers probably have insurance (and tries to explain what insurance is) when Superman says
"They will never get planting done by the crop deadline. "
Lois, not knowing what Superman is talking about, asks "what's the crop deadline?"
Clark, realizing exactly what he said, panics and fakes hearing an emergency to make a hasty exit.
