If you thought there might be a profession left on Earth where one might be excused from blogging, it looks like you were wrong.

David Skok of Matrix Partners now has a blog, and on Sunday he posted his second entry on it. Skok rarely speaks to the media, doesn’t hobnob at tech events, and toils in what one blogger has likened to a VC tar pit. He’s late to the VC blogging game. My guess is that Skok once thought it would be enough to simply pick good investments and help manage them to successful exits.

As a news reporter they give me a pain in the neck, but I’ve always had healthy respect for the old yankees who wanted to be in the news no more than three times: at birth, marriage and death. That attitude may be going the way of the right whale and cod stocks.

However, as a blogger, Skok, who is an investor in CloudSwitch, Solidworks, VideoIQ and HubSpot, among others, has so far done more than add to the noise.

He launched a site in October called For Entrepreneurs. It includes some standing resources, and a blog, on which Skok has so far avoided promoting portfolio companies, broadcasting what music he likes, advertising consumer goods he has bought, or offering musings on web services he is adopting early. He is winning my confidence as a reader.

His second post came on Sunday. I think it goes beyond what even some of the best VC blogs typically do. In it, Skok offers an equation and a spreadsheet tool for measuring viral adoption. Elements like ‘viral cycle time’ – the period that elapses between one user sending an invitation to the service, and the second user‘s adoption – show that Skok put some thought into getting significant results. More than management-guru advice, here is something a founder can pick up and put to use in a way that might help her company win.

If Skok is aiming for Internet celebrity, he’ll probably be disappointed. Other VCs have gotten there first and will likely maintain their healthy lead in eyeballs. But I don’t think that’s what he’s after. His first couple of posts here seem to meet a standard best articulated by Dan Primack, who blogs at peHUB – to be “moderately useful.” I wish more bloggers would reach for that goal.