Great trick to achieve Sidechaining effect using just Autopan effect. What's the point ? First of all, you can't freeze (which means saving CPU) the track which has Sidechain Compressor active. Second, "Autopan Sidechain", if saved as Default Autopan effect is probably few times faster than setting up a sidechain.
Personally, I see this as "quick preview" effect which almost instantly can be added to every channel.