You’re cutting yourself a single slice of cake. You grab a butter knife out of the drawer, hack off a moist wedge, and munch away to your mouth’s delight. The next day, you’re cutting forty slices of cake for the whole office. You grab a large chef’s knife, warm it with hot water, and cube out the sheet cake without causing too much trauma to the icing. Next week, you’re starting at your cousin’s bakery. You’re supposed to cut a few thousand slices of cake, week in, week out. You suspect your ha...