On Saturday morning you may have read Matt Stoller eviscerating my Washington Examiner analysis of blogger-backed primary challenges in 2006. He's since offered me this chance to explain and expand here at MyDD, and I appreciate the opportunity.

First of all, I would like to separate the op-ed from my day job, writing Hotline's Blogometer. Matt advised you to take the Blogometer with a "massive grain of salt" from here on, but I think that's unfair. My op-ed took a clear position and gave advice; the Blogometer's purpose is to give an overview of the political blogging scene. When I do make arguments there, they're generally descriptive rather than prescriptive. So I just ask that you judge the Blogometer based on the Blogometer itself.

Next, I will concede something: I was not fully informed when I wrote that that no national groups had endorsed the strategy of targeting incumbents -- I was not aware that the AFL-CIO was already backing Ciro Rodriguez. However, the MoveOn endorsement didn't come until the day the article went to press, and the DFA endorsement wasn't in the Hotline until the day after. Had I published this independently on the web, I would have had strikethrough tags at my disposal -- advantage, blogosphere. So I may have spoken too soon: Apparently Democrats are getting into Club for Growth-style primary challenges. And as I'll get to below, I think that could be a mistake.