ps. Anyone know what a "deadman" is in construction parlance? Answer will follow.

It exists in medical physics, too. When I'd first heard it, I'd guessed it was borrowed from heavy equipment operations of some sort. It's the switch you have to hold down to keep the gantry moving when setting up a linear accelerator for a radiation therapy treatment. Presumably if the gantry squashes you unexpectedly against the wall, you let go of the deadman , and it stops squashing further.