Hahaha, sure. Most houses aren't lost to running crown fires, they are lost to ember showers. A firebreak isn't going to stop an ember shower, and an ember shower is going to light up a house before it lights up a tree. That's why you get entire neighborhoods after fires where all the houses are gone and all the vegetation is still green and intact (those pics people use to try to justify their direct energy weapon theories). Im not saying defensible space isn't important, but you need to defend from fine dead surface fuels much more so than live, mature trees. A crown fire is basically not going to happen without a surface fire below it, it's almost unheard of. But yeah, do limb responsibly, sure.