Just quickly on this point (as you say we are on our own deadlines, but appreciate the input). This is true, wiht any network you can get in early and have more chance of a takeover. However, here as the networks grow the sections grow and dilute such early attackers. So the cost of attack will continually increase as you will need to add more nodes. But for sure the earlier this attack the better for that attacker.
I really just forwards messages. Vaults in the route will know nothing about it, but the destination group will need to know the authority of the mutation request (not for Gets, only for mutations).
Anyhow I just noticed you received a bunch of links below your questions. However we are aware our docs are lacking in areas, so please feel free to critique, poke around and try to find flaws. It is what will make us all better. So balance reading and poking, we do appreciate it all. At time I will answer fast, with typos and possibly seemingly abruptly, it is just being busy, so pull me up if you thnk I am too abrupt of quick with responses. We are an open bunch of folks so no worries and thanks again. Happy reading.