1) No, XIM NEXUS is the controller that is providing input, so, there is no additional communication with the console controller for that purpose.
2) You can, if you want, connect a hub to your XIM NEXUS Adapter and plug the console controller and XIM NEXUS Controller into that. But, that'll only save you average 2.5ms of latency. If you plan on doing this, let us know since I'd like to confirm that is still working in latest builds.