[gojomo]

Nice. A gray evocative of either look was my first thought as well.

It could also be half-and-half -- for example a diagonal cut. (Then the transition to the actual could wipe the wrong color off to one side.)

Or, a shaded gradient, top to bottom, between the light and dark -- so either way the flicker-to-actual is half as harsh. (This could also work well with a fade/wipe to actual.)