Working by reflecting the flash makes sense. Arizona is getting ridiculous. No one can drive without having protection on their plate. Cops say the product does not work. Yeah … like I would believe them. Anyhow, it seems your experience confirms my prior comment: for the instant that a camera flash shines, the light produced is blinding, preventing the human eye from discerning detail for that brief period. Similarly, it would cause an extra reflective license plate or tag, that reflects all that extra light to be overexposed in a photo. Your independent tests make sense to me and explain why the product sells so well.