I plan to completely ignore any and all trollish behavior, while occassionaly and at descretion responding to substantive, if dubious, claims made by offending posters. Since the poster in question makes very few substantive claims, this is no great burden.
Is this considered to be in violation of the agreement? That is, responding to non-trollish aspects of an offending user's posts? Or treating claims by offending posters matter of factly for the purpose of dispassionate refutation or dispute (effectively removing them from the context of attempted disruption, if even they might have been put forward in that context)?
Personally, I don't see how it could be a violation. But if an alleged troll says something like: "All who believe in evolution are Marxists; furthermore there are no transitional fossils," I don't know why you'd respond to any part of such a post. But that's up to you.
I see no problem with posting a rebuttal to non-trollish aspects, though it may be a good idea to be particularly detached in tone. Even so, a flame might ignite.