You're wrong. Security through obscurity is not secure. You should
assume that the enemy knows everything about your system except your private key.
When an uninitiated thief breaks into the house of a security conscious homeowner, he has no idea where the valuables are kept.
Actually, he probably knows where the valuables are kept, because the average person is stupid and predictable, even when they try to be clever (this is true of hiding places for valuables, and doubly so for passwords). It'd be much better if you could instead stick an unbreakable safe in the middle of your living room.