During my college years I worked as a Lab Tech at Lenscrafters. Five days a week I would find myself working behind a large plexiglas window helping other people see. This large window is a trademark of all Lenscrafters stores as it allows customers to watch their new eye wear get made, but it is easy to forget that that they are also able to watch you. I can’t recall how many times I looked up and saw a customer looking at me weird due to my behavior. Luckily, most of the time it was harmless laughs and snickers, but occasionally I would get a dirty look.
That simple plexiglas window gave me an illusion of privacy that simply didn’t exist. This is something we try to accomplish with the use of a one-way mirror in a usability lab. It isn’t the same though, because though mentally the participant knows there is someone on the other side of the mirror they can’t see them. I wonder if it would be possible to completely do away with the one-way mirror and show our complete hand. It may be discomforting at first, but speaking from personal experience, it doesn’t take long to forget that the window and people are there.
The usability laps I have had experience with had either separate rooms or one-way mirrors. Have you seen any other configurations? How would a single see through window effect your tests? Have you ever got caught while thinking you had some sense of privacy?