Fire management is all about energy management. A major fire like that in tall standing trees, fueled by a decent wind, is going to jump most fire breaks if that is all there is. Not only that, a major fire like that literally creates its own weather at the fire front, drawing air into the fire and throwing sparks a long ways.
However, if you can break the energy of a fire by eliminating fuel, eliminating velocity and laying the fire down, it becomes controllable. That means pushing the trees farther back and giving a fire more time to loose its velocity. In this case, there really wasn't any place to lay the fire down and break its energy, and that fire had a lot of energy. Thats what makes these fires so hard to fight is you can't ever attack them directly, you work on the flanks, cutting into the intensity until you can stop it at breaks.
those trees and shrubs next to the houses were just tinder. Yeah, had those houses been stone and non flammable roofs without trees and shrubs, many might have survived, especially in the center and far side of the division.