So most people are probably familiar with the idea of using blinds and dummy blinds to simulate fog of war. The problem is how do you determine when an enemy is allowed to see your unit if you if don't know which of their blinds are actual units?
Simple, at any point where an enemy blind is in line of sight of one of your (real or dummy) blinds you can ask for a sighting check. Both players close their eyes and reveal the label on their blinds. Then any player who has actual units opens their eyes and reads the other person's label.
This way if your blind is a dummy you won't know if the opponent knows its a dummy or theirs is a dummy too.
If your blind is concealed in terrain cover you don't need to reveal your blind whether or not it is real.
So imagine you are moving some armor along the edge of a first in which the opponent has a blind. Your armor is a blind in the table and you revealed it to them. You don't know if they saw it or not because you don't know if their blind is real.
Their blind could be nothing, it could be a harmless forward observer, or it could be an anti tank team that is going to blast you when you get close! If it's nothing, they don't even know you have armor there.
This may sound like a lot of overhead but as soon as a few models are placed on the table you won't have to do many closed eye checks because if a physical model gets Los to a blind you can just reveal it unless it is in concealment.
Does anyone else do this?