No single method is completely fail-proof--alarms, dogs, firearms, and your own health can all fail in high risk situations, though the risk of them all failing at once becomes exponentially less likely the more methods you have. The cops could get into cruiser crashes responding to the panic alarm. There's no telling what could go wrong. So to say an alarm or a dog is not a good idea is simply false--I think they're all a good idea, but the bad idea is relying on only one or two of the methods alone, to the exclusion of others, thinking it will save you.
Alarms are good for one's own warning letting you know the home has been breached, but as for response, bear in mind the hundreds of false alarms to the one real one means that the dispatcher is sending officers to that domestic disturbance down the street if the shift is short handed that day--and even if they can go, they're not breaking any land speed records. I've seen occasions where burglars have given Purina to the growling GSD and proceeded to ransack a home unencumbered. Firearms can malfunction and if you can say with absolute certainty how you'll react under such high stress without expeirienceing it before, you're either a liar or you're extremely naive.
No hypothetical can adequately describe or recreate every nuance and feeling that occurs in these events. If the person is in the basement, I might wait a few seconds at the top of the stairs before proceeding down to asses the threat. Some might disgree and argue that requires and immediate response, but it really depends. Can you descend your stairs with concealment of walls or do your stairs descend into an open basement? Do the door hinges creak loudly or quietly allowing you to make such an assessment silently?
With that said, I agree the very last line of defense when eveything else has either malfunctioned or been ineffective is you and you alone. Not the police, not your dog, not your alarm. And I'm in my home when someone who is armed invades the sanctity of my castle threatening my family with deadly force, I will defend it hell or high water--but will only effect the least amount of force necessary. While I agree it's indeed better to be judged by twelve than carried by six, I certainly don't do a helluva lot of good to my family if they can only visit me on Sundays from 1-3pm. Yeah, they're alive, but what kind of a life is that--for you and your family?
Do what you have to do, but only what you have to do.
[/rant]
That was no rant - fail. What it was though, was some very useful insight - win. Thank you!
To the rest of you 911-ers, I think the trouble with 'hypotheticals' is just that. We'd all like to take a stab at what the best scenario is for us. The problem in my mind with the "funnel defense" is just that - no offense. If it's a single intruder, busting in that final door containing you and your family, I suppose you have a shot, (pardon the pun) - but you've now allowed a threat within shooting distance of you and yours - hope your first shot counts. If it's indeed a home invasion and you have multiple armed shooting threats in your 15x20, then you'd better be adapt at neutralizing multiple threats at 2:18am, in the dark, scared shitless, with your trembling family in the line of fire. Audio exclusion, (myths and facts) aside, there's not much science written on visual exclusion, (different senses and principles) - there's going to be a bright flash on your first shot. Are you going to be able to see to make a second? Beats me. But you have now let your enemy inside your perimeter - hell, you've let them inside your defenses... Hope you can hold them off until the calvary arrives... Again - roulette. Not a game I play in casinos and not one I'm going to play with my family. Will I call 911? Of course, but will I hunker down in my bedroom waiting to see how many people are going to kick in my door and start opening up with my child in the room? Yeah - that would be a no way...