BTW, the only connections to the RPi are: power, router, and 2 output USB cables. I have the Pi set up as a dual jmri server: one instance is running as a LoconetOverTCP server, and the other is running as a WiThrottle server.
I connect to the first instance from jmri on my laptop using a LoconetOverTCP connection. This gives me a wireless connection from the laptop to the layout via the router (which provides a dedicated, offline network for layout use only). Note that this setup does not require a Digitrax layout; you can use the Loconet architecture as a command bus for stationary decoders, e.g., all the RR-CirKits boards, without having any Digitrax hardware whatsoever (other than a bit of generic Loconet cable).
I connect to the second instance from phone throttles in the usual way. This segregation has been working very well.