So, does anybody else find it weird that neither Rand's patrilineal ancestors (nor his mother, as Andor's requisite training in the White Tower would have undoubtedly detected even the potential to learn) nor his descendants through Aviendha after the first über-channeler generation could channel? None of them have the inevitable ability, and in some cases (Coumin, Ladalin) it is specifically mentioned that they could not even have been trained.

Incidentally, how does the forward-seeing ability of the columns work? It's one thing when it looks to the past, since people only have one father or mother, but even in a deterministic universe, people can have multiple children. Why does Aviendha's vision follow Padra, and not Marinna?