Shameless plug... (see what I did there?
)
Sidechain Mixer gives you some additional routing options, like sending from a bus back into a track. And of course you can also route from track-to-track to create a track bus.
So in the example where bouncing from a bus to a track would be required, you can simply drop Sidechain Mixer into the track's FX bin and route the bus output back to the track in realtime, no bounce required.