Yeah feel like it's similar to don't look down the barrel of an unloaded gun. Sure, there's not supposed to be a bullet in there, but the risk if you're mistaken is too great. There's not supposed to be a train coming down those tracks, but would be pretty bad if there was.
I'm sure you're right. I guess my example was because even if you're certain that the chamber is empty because you cleared it yourself, you still have an inhibition about looking down the barrel. Even if logically I knew no trains were coming, I'd have a hard time sleeping there.