When I am awakened in the night by an out of place sound, I do wake my gf if she's not already up and I arm her before I exit the room. When I do exit the room, I stop outside the room and listen for any sounds before clearing the house, I don't just rush into whatever might be waiting.
Right. So we are discussing several things here and they are all related.
1. Strategy
2. Tactics
The safest, most conservative and all-around proven thing to do when you hear a bump in the night is to arm up, take the defensive spot behind the master bed and keep the guns trained on the locked bedroom door while dialing 911.
I'm never doing that unless I hear voices and crashing furniture on the other side of the door. In all cases that actually have happened here so far, I get up, grab a flashlight and go check out the noise. "Clearing" a house in my circumstances usually means ensuring the doors and windows are locked and secure.
Any repeat of the noise or additional sounds of any sort would radically change everything. Probably go for the gun at that stage.
As for tactics, you know how in the horror movies when the people decide to split up and you're shaking your head, saying out loud, "no, no, don't split up, stay together!" well that applies here. Once you've decided to go armed, stay together. Either stay put together or go investigate together. If you're now clearing while armed, you have double firepower and double clearing tactics available.
Even if the wife has only 200 rounds of shooting experience, that's plenty enough to point at a BG and open fire. The error in strategy that led to this near-disaster involved splitting up the team, who need to either stay together or remain in communication.
Per hso, however, SWAT practice or whatever isn't much of a factor for the average home defender. Far as I'm concerned, if a highly trained team of coordinated gunmen with automatic weapons plans to breach my home and execute me on sight, I'm already dead. I've done something seriously wrong to piss off the wrong people. The shooting is the aftermath. They could lay in wait in the garage and get me while I'm going out for the paper in the morning. They could booby-trap my car.
So my primary defense is to avoid having large armed teams of executioners come after me. Training to defend against such an attack is a separate matter from general home defense against robbers, rapists, serial killers, etc.