Any Seo Benefits to creating a blog & giving sub-domain blogs to others that're part of main blog

I wish to create a blog and then give others a subdomain that is part of main blog, just curious what are the SEO benefits to the main blog if those subdomains that are being given away are adding their own content to their blog...

Example below:

www(dot)xyz(dot)com

edwin(dot)xyz(dot)com

The question I have are there any SEO benefits to those that I give a duplicate of my site blog, and they are adding their own content to the blog.

by doing this will this give any type of seo power to the main site, and will the search engines look at the main site a authority site, due to all of the content that is being added to all of the subdomains which tickles down to all those that get a free subdomain where they are addding original content to the site.

There is a company called empower network they have a system called kalatu blogging system which they issue to people who join their network, and they say it is a authority site, they state that their blogging system that people get from them I believe is a part of their authority site that helps them rank for their keywords when they are blogging on their system.

So I am trying to understand why is this so, that the kalatu blogging system that people get from them gives them an advantage when they are blogging and trying to come up on 1st page.

Trying to figure out if i should just join their kalatu blogging system and refer team members to their blogging system.