Yes. . . that demotivational poster.
Funny as it is with that caption, Kei told me that this is an actual maneuver and is used as a counter-measure against flash/stun grenades, keeping one eye covered to protect against flash and the other open to keep tactical awareness of the situation. However, considering the advancement of lens technology and those ballistic shades that feature anti-flash lenses, I imagine this maneuver has run obsolete.