FYI, Carl's older videos dealt with a workflow involving synths being managed by Carla. That's probably what you're thinking of. The video I linked is more current where he's brought the synths back into Qtractor itself which has many benefits including simplified routing, improvements in patch management (in the case of ZynaddSubFX at least), and more. Carla's role has been seriously reduced to simply providing pass-thrus for the purpose of working around the known issue where Qtractor doesn't work when you connect a bus' output to another bus' input (when running Pipewire. The "session management" is virtually nothing compared to the previous workflow where Carla was used as the instrument host. Glad to hear you're not experiencing issues though with the Aux-send approach. If it ain't broke, don't fix it! :)
FYI, Carl's older videos dealt with a workflow involving synths being managed by Carla. That's probably what you're thinking of. The video I linked is more current where he's brought the synths back into Qtractor itself which has many benefits including simplified routing, improvements in patch management (in the case of ZynaddSubFX at least), and more. Carla's role has been seriously reduced to simply providing pass-thrus for the purpose of working around the known issue where Qtractor doesn't work when you connect a bus' output to another bus' input (when running Pipewire. The "session management" is virtually nothing compared to the previous workflow where Carla was used as the instrument host. Glad to hear you're not experiencing issues though with the Aux-send approach. If it ain't broke, don't fix it! :)