Is domain redirection a good method for SEO?

[solutionfallco]

I have a question and need suggestion from you guys. I’ve searched for my question on Google but don’t get exact information what I need. Maybe I can’t search perfectly.
Let me explain my confusion:
I’ve checked backlink profile of a website. He is not using his main domain while doing comment backlink. He put his another domain while doing comment backlink. The another domain redirect to the main domain.

Why he use another domain while doing comment backlink?
Is it helpful to get better rank on Google?

For example: My Main Domain = solutionfall.com
Another Domain= xyz.com (It redirect to solutionfall)
He just uses xyz.com while doing comment backlink.

Thank You so much

[Sriram Chennai]

Yes. I think so.