Bfreedma, I totally agree with you, but the problem with that is that a dozen or more people have to modify their participation in the group to try to discourage one troublemaker. And Gregorio is a tremendous asset to the group, but this isn't his particular strong point. It's simpler to do what Castle just did and cut off the bad apple.
I agree that he was an obvious troll. I think we've seen him many times before under different accounts. I often see them enter threads continuing arguments from the past that I don't even remember. It's difficult for all of us to all be on the same page as to which idiot is the troll and which ignorant person isn't. I can discern the difference pretty well because I've been on the internet since usenet days, but some of us aren't as good at that. I think it's easiest to just call someone a troll who outright refuses to play by the rules of the forum (i.e. science) and refuses to treat the regular participants in this group respectfully.
It's a difficult problem and I think it's best dealt with quietly behind the scenes by the mods. Thank you Castle. I know it's frustrating. Here is a virtual cake for you.