I dont handle my eggs rough at all, i just know that it isnt best to do it at that stage. A lot of people are quoting me for this, the reason im saying dont handle the eggs at day 18 is yes, because of those reasons and because you should be extra delicate. Its more so developed then the other times, i wanted to make sure they know not to candle it past that aswell. Some people say you can, others say you cant, its just what tou prefer i suppose, theres just a few more accidents with doing it that way i think.