Let's say I have a money site, call it MoneySite.c0m. I also have a Tumblr blog where I network with other Tumblr users to get them to follow the blog where I post links to my money site. My money site doesn't have that many backlinks but my accompanying Tumblr blog has TONS. I've managed to give my Tumblr blog a custom domain but instead of registering a new domain, I've now made it a subdomain of my money site, let's call it blog.MoneySite.c0m. Would this boost the domain authority of my money site in the eyes of Google?