Is ActiveRain Better For SEO because of its Domain Authority?

I have a couple of ActiveRain accounts. Grandfathered in from the "free" days. I maintain a presence there but I always treated it like a part of my SEO support system, not as a destination. Nontheless, posts I place there have extreme sticking power compared to some carefully supported posts on my own blogs. I'm going to begin targeting my account for some of my keywords, just to see how it ranks. Given its higher parent domain authority, it will be interesting to see how this community domain bolsters my own back-link results compared to my lower PR blog. With Orange County SEO being my primary target, We'll see how this established blog performs.