How does the Cull Area utility script work?

I saw that a Cull Area script was recently added to the utilities folder. I started playing with it in my scene and looked through the code, but I'm not sure if there are any additional steps required. Do I have to manually subscribe objects to it for them to work? Or does it handle everything by itself? I'm guessing this is similar and/or is this http://www.m2h.nl/network-traffic-culling/.

https://gyazo.com/9bb135eea50d0b10b4831c181847eaee
https://gyazo.com/f356d59c15bb3b2636df8e7ecfcc7c0a