Just by chance, I read this article after I have written the previous post on "Cheating a Bit .. ".
WIRED Feb-11 Cheat With Science. So, the cheaters need to be able to lie and know about the theory that a person's brain works harder when they are dissembling .... and that this extra cognitive load has physical manifestations: one of them let them wear shades.
In addition, do not give indirect incentives and collect shades at the porter's desk.
