Sure, envision connecting two DCS channels to the same track, that's crosstalk. That happens as you cross channel boundaries, but having them connected all the time would play havoc with the DCS signals. The 22uh chokes are to prevent that from happening. Since one ZW is powering all the yards I'm working on, without the chokes we'd have problems.
How could you have crosstalk when the DCSRC is only being used to generate a watchdog signal?
I've been using a DCSRC to generate the watchdog signal on a unpowered siding where locos are parked for a few years now with no problems. Siding is wired thru a toggle switch that connects it to the mainline. DCSRC is wired to siding in passive mode. Throw toggle to power siding on, watchdog signal is generated, start loco and run out onto main.
Talking about the DCSRC...didn't I read somewhere that it will be updated to run any loco regardless of address?