Seems like a much better idea is to have some kind of imperceptible "this is forged" symbol on the saved file and anything exported. Even a dumb criminal could

Seems like a much better idea is to have some kind of imperceptible "this is forged" symbol on the saved file and anything exported. Even a dumb criminal could get around this with another photo-editing application. With the latter they'll get caught and not understand how. And legitimate uses like the author's aren't affected.