Great article. I would mention one thing from personal experience, however. I never had any luck marking eggs under a broody hen and removing unmarked ones. Inevitably eggs get broken or pushed out. Also, broody hens are notoriously dumb about getting back on the right nest after an eating, drinking, defecation and exercise break. If there are other eggs/nests around, she is just as likely to get on them instead and let her own developing eggs chill and die. It's best to move her into a separate pen or perhaps a small separate coop. She may resent being moved and quit, but usually not, especially if you do it at night. But I've found that leaving her in a nest in the main coop with other eggs being laid is almost a guaranteed loss. Waterfowl cannot be moved, but fortunately they aren't dumb like chickens about getting back on the right nest.
While it is a good overview, I disagree with feeding a chicken or rooster raw egg, they are more likely to become egg eaters you cannot break of it and end up culling.
Some great facts in there! Good to know that fertile eggs can be eaten early on after laying - I was wondering how you could tell what ones were 'eaters' and which ones you had to avoid!
I never thought to even looking into the information you provided. The only thing I looked into "lash eggs", which is an inflammation of the oviduct where the eggs begins its travels. They are not true eggs but may contain bits of egg material and a lot of pus and other material. They are rather disgusting and odd. If you want to see one I've attached a pic.