CRA over a bua simply cannot be condoned. Anything could happen. A pilot could become ill. His elderly aircraft could hiccup. His ground crew might make another mistake. A heron might get in the way. So many unknowns. It is not safe to assume that all eventualities have been considered. You have to look also at the possible consequences, hundreds of people dead, a whole town infrastructure demolished. That should not be risked, however low you might think the risk to be.