Col, as uncivilized as we are over here in the (former) colonies, we CAN learn.
We evacuate because the weather forecast models are getting much better. We can correlate the predictions to pictures of various storm intensities. When the National Weather Service says we are going to get storm surges in a range that includes good odds of overtopping the levees, it is time to leave an area.
George, I can truly, honestly relate to your situation. We were lucky, too, as Gustav missed my neighborhood mostly. Just some downed power lines with no predictability as to which neighborhoods. My stepson, about 2-3 miles from us, lost power. So far as we know, our microwaves never even starting blinking. For us, power was continuous.
Our bigger concern was for what COULD have happened. (Col, you can read this - it might explain to you why we evacuate.) My mother-in-law has a degenerative back condition. We evacuated so we would have extra time to take care of a little old lady stuck in a wheel-chair or walker. When dealing with the handicapped, it ALWAYS takes twice as long as you think it should to get everything going. But you do that gladly for your family.
Of course, we also know about Katrina and her aftermath. Gustav could have been another Katrina if it had hit New Orleans square on instead of jogging west towards Houma and Lafayette first.
Glad to hear you're OK, George. Been there, done that, bought (and wore out) the T-shirt.