This actually helps a lot. I saw, probably you, post on the colors that go into cx before that's why I was unsure of the possibility of hatching white.
The mottled nn and laced polish I would just figure the colors were the same most likely come out like the mottled rooster, shows how little I know Lol!
The giants, I have one hen that is what you described 'dirty' white, couldn't cull her cause I was severely limited after obvious culls, a hawk and a split hip on two of the nicer pullets, and she is huge, almost as big as the rooster still. Funny thing was she actually was as she got over a yr old she was a lot white and then they molted, when her back feathers came in like a patch of dirty white like a saddle Lol!
My first hatch (should have hatched more...) was mostly cockerels, ended up with only three pullets to add and the biggest one also 'dirty white'....
So... I think I'll go with crossing in a good quality black, will be easier anyway. There is a BYC member not far from me that has been showing his birds, blacks, and has good quality stock.
I was just a little leary of it after reading this;
http://nationaljerseygiantclub.com/media/Document_10.pdf, but they didn't go any further with it.
Thanks!