I guess I'm stupid. I thought this was the way it worked all along. I didn't realize it was a controversy.
Me too. And what they were describing as the old theory of a small class of ruling elites is what I thought the Norman conquest was all about.
When it came time to invade what had become England, William took with him an army composed mostly of men from the Norman and Bretagne coasts, and down to Anjou. That is, his army was made up of folks who were primarily descendants of the old Briton refugees who came to Brezh in the 6th century. His very first "Norman" town was called Vauxhal, which is simply the way a French speaker (William) would spell the Gallo name of the county seat of Normandy at the time, which is, itself, a short form for "Carvajal".
This is undoubtedly the source of the Briton input among the Danish and Dutch populations that nowadays dominate so much of the life of the British Isles.
No doubt the Anglo-Saxon heathens put as many Britons to the sword and spit as they could. We should all be happy William put a stop to that nonsense.