As a former sparky, I am ashamed to see that. But I have always contended that it is the plumbers who should have special CE courses in the proper use of power equipment. I definitely see a whole lot more defects caused by the pipe guys than by sparkies. Or maybe, from the point of view of the plumbers, we should just take it all the way back to the architects whose designs cause that joist to be positioned directly under the tub drain?