If you hadn't mentioned this, I wouldn't even know that Authorship could be associated with just a directory. I bet a lot of people, including the OP, fall into that category. If the OP just associated it with his onsite blog (/news/), then essentially the only purpose of Google Authorship would be promote his company blog, not his overall site. So he would be G+ blogging to promote his blog to promote his products. Sounds a bit convoluted to me.