Wow! I would hate to meat that girl in a dark alley.
If you left those eggs to become chickens, would two chickens come out of the same egg? Or just one? Or are they not viable?
I have been told that they are not viable, so you cannot breed a double yoker as such.
She's actually quite a young small hen and only just come into lay and the eggs themselves were not even large ones. Sadly I expect this is just young hen stuff, but it would be great if she continued this way - they made a fab breakfast for the family