...that guy was in the throes of a psychotic episode [1]:

  The long and full apology is inserted below. [...] He (?) also says he suffers from schizophrenia.
  I’m happy for “Al” that he’s getting help and tries to move on. For me, this apology at least finally proves that this threat is over and in fact never was intended literally. I hope I will never receive anything close to that again.

  The apology in full
  I am Al Nocai. When I contacted you initially, I believed you to be a Dan E., from texas, or a Dan S from delaware or a Dan from Minneapolis. I didn’t do my research, and when I found it was actually you and you had nothing to do with my situation, I became indignant and even more of an asshole. You had every right to be mad, and publish as you did. I’m not trying to justify what I did, there is none, I should have been a lot more cordial. I just want to provide context around what was happening, I believe I at least owe you why.
  I had to retire from my career do to schizophrenia. Again, I should have not let my delusions go to the point they did nor should I have acted the way it does. My illness doesn’t detract from the rashness of my actions.