Trolling is defined as an inflammatory post used primarily for the purpose of irritating other members. Examples of trollish behavior include ... making offensive declarative statements ... and making personal accusations towards another forum member.

I and perhaps many other members did not see the other threads. What difference do the other threads make? I take your first post as "making an offensive declarative statement" as well as "making a personal accusation towards another forum member". You've decided that the member is a troll and his or her future thread will be trolling and you've singled them out as a troll- ie making a personal accusation.

I find you normally well above such stuff, but IMHO creating a thread to call someone a troll is trolling itself. Maybe the person deserves it, IDK- but that call is not yours to make unless you are a mod.