"...You can usually get a perp's attention with the sound of a slide jacking a shell into the pipe..."
Racking the slide to "frighten" a criminal is an urban legend and is amateurish firearm handling. If one doesn't store the shotgun with a round already chambered, it should be quietly loaded without providing additional warning to the criminal. One can choose to "challenge" the criminal if desired, or they can wisely shoot them where they stand. A person who enters a home via the roof or window in the middle of the night isn't visiting to have tea and butterscotch krimpets.
Research on this topic will quickly show you that respected firearms experts universally recommend against the "Hollywood" technique of loudly racking the slide in the presence of the criminal.
~ Blue Jays ~
That's kinda hard to do too. I'm not even sure how I'd quietly load a pump-action shotgun even if I put a shell directly into the pipe so I'd only have to move the action in one direction. Which explains the .357 revolver in my night stand.
Your point is well taken. However, I would assume that the homeowner knows the inside of his castle better than the intruder. Secondly, since the homeowner was awakened, he probably has a good idea where the sound came from. That being said, the home owner could lie wait to ambush the intruder. Now, lets deepen the scenario. What if there were other household members that just got up to get a glass of milk, midnight snack, etc. unbeknownst to the homeowner. Does the homeowner shout out and summon up a challenge as to "who goes there" and give away his position? Or does the homeowner fire in the dark?
My original statement regarding racking one into the pipe sends a strong signal to the perp that you are armed and probably the second sound the perp hears is the gun being fired. Also, if the person walking around your home happens to be a family member other than your wife, you have probably just avoided a nasty accident.
To come upon an intruder in your home is dangerous enough especially when the perp thinks you will not respond. But to lay in wait quietly, a blood thirsty lawyer may consider that your actions were premeditaed.