I do not have a very stealthy car right now, so it probably would not make a difference (it is white). However, my next car will be black and I do not have front plates. Also, I tend to drive long distances (NC to FL -- I95) and do so during the day.
Many sports cars in the past had flip up headlights and we know this greatly helps with laser stealthiness. I am not sure about the legal issues so maybe someone can enlighten me there. Nevertheless, what do you all think about putting some sort of completely opaque (black) tape over the headlight lenses, for daytime interstate use only. Or if you wanted to you could take it a step further and could fashion some sort of lens cover that looks like the smoke ones but is complete opaque for daytime use only.