Pete,
Do you really believe that a Biarritz in an interpretation of the valley of sin? Granted I wasn't there, but it seems to me that the origin of the Biarritz green was the landform of the tee shot over the bay. I can't help but think Willy saw the huge drop down to the bay and thought it would be neat to make a green that reflected the entire hole ala high low high hole merits high low high green. I think CB liked the playability and incorporated as much as possible scewing our understanding of the hole origins. Perhaps any hole that has a green which, to use the musical term, recapitulates the overall hole should be a Biarritz, no?
Cheers!
JT