7/31:  update here.

I need to correct a mistake in  one of my comments about the Tom Johnson business.  Here's what I said at first (July 9)--
Not only does Chris know the identity of Tom Johnson, but I think he's being a bit modest about what he had reason to believe in 2009.  The student provided ample well-corroborated detail that made it clear he could have witnessed just what he said he'd witnessed. Granted, "William's" credibility is zero right now, so who really knows what he witnessed? But at the time William/Tom Johnson/X sent that email, back in October 2009, his story were believable.
That was exactly what I wanted to say, but in response to lots of questions and attacks, I tried to find a way to make myself clearer.  I said (July 10)--
#6   Some are quite confused about what the issue is.  It's not whether the mystery person is generally credible. Of course he isn't.  It's whether Chris Mooney properly vetted Tom Johnson before elevating his comment in October 2009.
Distinguishing between  "proper vetting" and "general credibility," or credibility now, seemed helpful and clarifying.  However, I'd inadvertently been more specific about chronology.

Now that I look back at Chris Mooney's July 9 post, he was clear that his "vetting" was in response to questions--
after some questioned his original story, I took the step of confirming his identity, as this individual provided great detail about who he was, where he worked, what he’d published, and much else.
So he elevated the comment to a post, then investigated in response to challenges, and received a confirming email.

I never noticed the "drift" from one statement to the next until last night. In retrospect, what I said in my original July 9 post was exactly what I meant. I was not trying to say anything precise about the chronology of elevating, questioning etc., none of which was relevant to what I was vouching for.  That was....well, just what I said on July 9. My first post is all I really had to say.

A new rule at this blog. We will never ever use the words "sock puppet" or "Tom Johnson" again.