Earlier quoted context omitted.
If the source IP is encrypted, the recipient needs to decrypt it first in order to be able to send a response. To decrypt it, it needs to either have some shared secret with the sender, or the sender needs to use the recipient's private key. The parties cannot obtain the shared secret the usual way, the Diffie-Helman exchange. It cannot be performed, because it requires back-and-forth communication, which we are tryi…
> but it leads to all kinds of practical problems, figuring out which is probably best left as an exercise for the reader. Any examples? I honestly don't see any problems here.
Throw onto that the trust issue - such IP certificate repositories are very quickly able to determine who is communicating with each other, and at what time. Whilst this is currently possible anyway, current methods are less centralised, more expensive, and more visible.
You'd have to go full onion