I doubt that he is a troll. Trolls usually show some intelligence in
adapting their responses, so as to keep the fun going. This one simply
fixates on a few sentences and appears unable to focus on anything out of
the immediate context of the original sentence. This inability to shift
focus to process new information is more a symptom of a cerebral handicap,
something like Alzhheimer's or Asperger's diseases or even early-stage
dementia. Unfortunately, there is not a great deal that medicine can do for
these problems. Perhaps his keepers give him a computer to occupy his
attention.

Internet newsgroups are wonderful (IMO), but there are not good mechanisms
to prevent one or two people from destroying an otherwise excellent group.
One can plonk the offender(s), but that still leaves all the responses
visible. I wish people would simply cease responding to him, since it is a
pointless exercise.

Bill