Point well made. Nit: meeting the requirements of law isn't barely collapsing; that requirement has so many safety factors built-in because the building code h

Point well made. Nit: meeting the requirements of law isn't barely collapsing; that requirement has so many safety factors built-in because the building code has to approximate so much. The approach isn't that dissimilar from how that "anybody" you mention would build their bridge that doesn't fall down: by guessing safely.