There's a lot less that can go wrong when you're trying to contain an explosion by distance, then when you're trying to contain it with dirt in the way.
Here was another oops moment, from an airborne test:
"Shot Harry was detonated on a 300-foot tower. The 32-kiloton explosion heaved a vast amount of earth into the air, much of it vaporized, most of it as a fine powder, all of it radioactive..."
My point is simply that it's hard to stay safe when within a couple miles of an energy release of that size, no matter what your model tells you. Downvote if you like; this seems pretty non-controversial.
