Well this is very interesting to me - I've been following along. I have a pair of brown chinese, and the female already has a clutch of 10 eggs so far. I had similar questions too, like how many will she lay in a clutch before trying to hatch them, etc and am impressed that they would lay such a large clutch. My guineas always had about 15 or so before they decided to get broody. I never see the gander and goose mate, so I have no idea if any of them are fertile. It has been over a decade since I had geese and I honestly can't remember much about the first group except that I left them alone and they made nests in my horse stalls and hatched a few babies here and there.
I never bothered with the proceedings of laying/setting/hatching with my previous geese, but since I only have a pair this time and not a gaggle (and they have their own yard and aren't free roaming the property) it is easier to follow along with the whole process. This is fun!