Sidechain with Aux sends only (less latency)

When we use Insert Sends then we get a latency penalty of one jackd period compared to an Aux send. This becomes audible depending on your jack period size.
There is a way to use Sidechains with Aux sends only.
Example:
We want to use Calf or LSP side chain compressor.
The snare drum shall "duck" the bass to make the snare snappier.
Snare track (with stereo instrument plugin) -> 4 channel output bus "snare" -> 2 channel master bus
Bass track (with stereo instrument plugin) -> 4 channel output bus "bass" -> 2 channel master bus
We put the side chain compressor into the output bus "bass". The plugin uses channel 1+2 for the signal to be ducked and channel 3+4 für the side chain.
So the bass audio will go to 1+2, that's what we want.
We cannot simply use an Aux send in the snare track to the bass bus because the snare signal would end in 1+2 as well. So we have to move the snare signal to 3+4, e.g with Carla patchbay 16 chan, then use an Aux send to the bass bus, then move 3+4 back to 1+2 with another Carla patchbay 16 chan.
This way we have the snare on 3+4 for the Aux send and on 1+2 for sending the signal to the snare bus.
Works for me.
Make sure that all other tracks don't go directly to the master bus but to a staging bus that goes to the master bus. Then you have the same latency because the signal always goes from a track to a bus that goes to the master bus.