(A) Yes it's early.  And the timing might be a coincidence.   But until there is contrary evidence, the timing says all to me.....  They posted once and only once about an hour after my ANI and attendant FYI on their talk page.  Presumably, they posted, saw my comment, and vamoosed.   The deal was sealed when an official ARBCC notice went on their talk page a couple hours later.   They've been silent ever since.  There could be another explanation, but per Occam's Razor I will need other evidence to think the ANI I filed was not the determining factor. 

(B)As for consensus, that certainly applies to discussions of sources and text.   Only JJ was (needlessly) agreeing with the assessment that another editor is too uneducated on the issue to contribute.  Which certainly appeared to be true.  But in my experience it's ineffective, laborious, and unpleasant for lots of other would-be editors when we approach such things by attacking WP:RANDY directly, instead of giving him the rope to hang himself through FOCCing and DR.  

(C)Finally, Stephan, you're an ed that ranks among the highest on my respect-o-meter, so I hesitate to challenge you with this but here goes.... You scolded me for discussing behavior on the article talk page.  JJ was talking about behavior on the article talk page.  Did you scold him, or only me?  He was agreeing with you after all, so I was just wondering if the goose and gander are in the same boat here?

In my closing here, unless something new comes up, WP:FOC .... WP:FOC.....WP:FOC....WP:FOC.......    I ain't gonna apologize for complaining when JJ does not do that, and I very well may complain formally if he does not stop.   Since I believe in prevention, not punishment, it would be of more help, perhaps, if you try to mentor him also.  Since my efforts have run out of patience maybe fresh blood would help, especially in terms of that consensus you were just speaking about?

Whether he accepts any advice you offer is up to him.  But I stand by my opinion he needs it.