There are threads about single yolkers how many you have gotten per day. How about how many double yolkers you have ever gotten? I have gotten 2, each from a different chicken.
My three Barred Rocks were double yolker queens, but only when they first started laying. They gave me 2-3 each. Then one of my three Light Brahmas gave me a double yolker, but I haven't had any from my Orpingtons or my Production Reds. Clients LOVE them!
I regularly get doubles, but one of my first eggs was a triple!
So far I have had about 10 double yolkers, and to tell the truth I'm a bit worried that the hen laying them has a problem. However, they are less than a year old so this might be normal.
I believe I have video proof several doubles, and of course, the triple.