“If you lay it flat,” says Bertrand, “you’ll put holes in the floor.”

“Possibly,” concedes Jacques.

“Furthermore, this will go faster if we both drill.”

“Perhaps,” says Jacques, “we should hold it and drill from opposite sides.”

Bertrand considers that, frowning, but he can’t find anything wrong with the idea.

“All right,” Jacques calls over the sheet of wood a moment later, “remember! We are bracing on the left and drilling on the right!”

“Yes,” says Bertrand, still frowning. “I think… yes.”

A few seconds later, screaming, they jerk back their bleeding hands. Unsupported, the wood falls over onto Bertrand’s head.