@benpate @hazelnoot tbh, the worst part is that there's a lot of federation behavior that is completely unspecified, except by loose implication in the C2S parts.
The division of C2S and S2S feels to me like some people wrote it in this way because it's nice to read. Describe a server to server protocol by talking about what happens
I can see myself doing that. Then the genius manager decision happened: We can call this two protocols and claim twice the fame.