Autor tilts his head. Clearly the gears are spinning. "Good point. Aside from creating a tiny"--there's that word again--"fuse, I haven't made any progress towards grenades that explode before impact. Hmm. I'll think on that."

Autor turns his back on her and feels his heart speed up in the process, lest she change her mind and blow him up from a distance. He walks about five feet away and gingerly--strange, I didn't have a problem handling this before--lays the grenade on a dry-ish patch of earth.

Then he jogs back to her and stands closer than before, with his hands resting on his hips. Marginally closer.

"Your move," he says, gesturing with the hand he's not using to adjust his glasses.