[diggan]

> Are you implying that we would assign a public /64 subnet to a collection of nanites that were designed to be absorbed after a week in the human body, and then retire that subnet forever?

No, I meant it as "You can reuse the subnet after 1 week + N" basically.

> it's just an intellectual exercise and take a stab!

Indeed it was, and thanks for conjuring a gratifying answer :)