Cabernet Sauvignon and Chardonnay: Where Did They Come From?

I'm rereading the Viticulture Lesson 2 by Andrew Walker, the UC Davis Professor of grape breeding and genetics. When I was taking the course and listened to and read his lecture, one of the points that he made escaped me.
Prof. Walker explained that using DNA markers called simple sequence repeat (SSR) markers, scientists determined that the parentage of Cabernet Sauvignon was Cabernet Franc and Sauvignon Blanc. The parentage of Chardonnay was Gouais and Pinot Noir. Okay, that's good to know, I thought. But, now that I am rereading Prof. Walker's notes, he goes on to add that the parents of Cabernet Sauvignon and Chardonnay are all hermaphrodites. That means that the parents are all self-pollinated and are self-fertile. In fact, the seeds that are found in these hermaphroditic varieties are self-regulating and very few produce viable offspring. Therefore, they are propagated vegetatively using cuttings.
Prof. Walker mentioned that at first, the crosses that lead to the Cabernet Sauvignon and the Chardonnay were thought to be spontaneous hybrids. However, in order for a hermaphroditic parent to contribute to the parentage of an offspring, it is very difficult and uncommon to get pollen to drop out of the anthers (the part of the stamen containing pollen) and pollinate another hermaphroditic parent. In fact, in order to create a viable cross, the stamen from one of the crosses must be plucked off and the stamen (pollen) from another parent must be used in the pollination.

Since Cabernet Sauvignon and Chardonnay are old varietals, it begs the question, when did these crosses occur and who did it? Fascinating!
1. The illustration is from the UC Davis online Viticulture Course. Dr. Andrew Walker's Lesson 2---Plant Materials.