That's so interesting, Moss, thank you for posting the link. I feel an urgent trip coming on to the motte at Sherrington. I mean they do caution that you can't start doubting the date of every motte in the land :) But Sherrington's firmly on their Interesting List.

Also, the bibliography has so many leads for more reading. There's a pdf online of one about Marden, also by Leary. So I'll make a link to that.