evens

You know the theory for how to get a piece of cake or some such cut evenly between two people? Ask one of them to cut it and the other one to pick. That will give the cutter an incentive to cut evenly and not cheat.

But what if - I was thinking while slicing brussel sprouts in two for B.'s dinner - what if the person doing the cutting isn't very good at slicing exactly in half? Then the cutter will be cheating him/herself.