.....it is a cool watch and you make a good case for a "grail" status.
However, I think the thing about the word "grail" is that actually such a thing doesn't exist. We all have specific watches that feel like they are grails but then, once we attain the grail it no longer becomes a grail. A bit like Schrodinger's cat paradox. Once a target is reached, its status changes. Once upon a time I thought that a Daytona PN was a grail. Once I owned one, I realised it wasn's a grail. So, in the context that I have stopped looking at any watch as a grail, do I see yours as the most desirable?
I think you provide a great analysis of why it is desirable, but how desirable depends on the value one places on history. The Daytona starts from, in my view, the 6239. There are so-called pre-Daytonas that might also be called Daytonas....6234. These origins have the history....they started it all. For the same logic that the 1665 Sea-Dweller will forever be the King of Sea-Dwellers in my book, the early Daytonas like the 6239 will always have an edge over any modern variant precisely because I place so much importance on the history. A DB5 will always be technically inferior to a DB7, but always more desirable for me.
Cool? Yes, without doubt. But THE GRAIL? Not for me, but that is just personal tatste.