Using Automate mute as a send

Hi guys, I’m trying to create mute automation on an empty track and send it to another track containing a synth. I’m attempting to insert a compressor on that synth track and send the mute automated track to it’s sidechain, triggering a kind of on-off effect for the synth. I got the technique https://www.youtube.com/watch?v=c88v2-C1Y4c where Dave Pensado recommends it as a technique. I’m having trouble working out why you wouldn’t just create the mute automation on the actual synth track itself though insteadof messing around with a sidechain, so extra creds to anyone who can not only explain how it’s done but why you want to do it. Don’t ask me why I’m so desperate to do it without a real purpose. It just bugs me not being able to figure these things out.