You have to join the gang at The Corner who just ignore him. He’s perhaps suffering cognitive deficits from weird viruses he’s exposed himself to over the years. An MRI of his frontal lobe would be revealing...Sarah Palin’s medical records will be fair game when his are (and Barry’s, too).
Yes, he has a fixation on the NR crew kind of like a rabid dog having a spell, doesn’t he? They do largely seem to have figured out not to bait him or even respond to him any more.