Yes, Poser is the tool I used to make the images for the article. As a means of visualization, I certainly do believe it can be useful in learning aikido. But that will depend on the learning style of each individual, and naturally is no substitute for the physicality of the real thing.
My understanding is that Poser was originally conceived as a life-drawing modeling tool for digital artists, much the same way as a human model or a wooden posing doll are aids for traditional media.
I find that when I try to create a realistic scene in Poser for aikido stances and interactions, it forces me to stand up, pose myself, and analyze deeply the posture and geometry of a given stance. In that regard alone, Poser can serve as a mirror, better in some ways than photos or videos.
On the other hand, aikido has taught me things that are often difficult to teach or explain in words. Tools like Poser help me bring that inner vision out.