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1 How would you deal with a user who produced a steady stream of valuable answers, but tends to generate a large number of arguments/flags from comments?
Argumentative attitudes and poor behavior are not and cannot be automatically excused because a user posts top notch questions and answers. My responsibility as a moderator entrusts me with making this a place that people want to visit and learn about the topic. Whether the post is good or not is irrelevant to users that have to deal with the poster's bad behavior. I realize there is a line between correcting and arguing, but I think in most cases the intent is clear. As a mod I could nuke the whole comment stream then leave a comment of my own telling them to knock it off.
2 How would you handle a situation where another mod closed/deleted/etc a question that you feel shouldn't have been?
I would first yield to experience. If the mod was a mod before me (for example, if both Caleb and I were mods) I would trust his judgement over mine. I would then use the opportunity to learn from him. However, inevitably, I would eventually consider myself equal with all the mods. I would definitely not confront another mod publicly about a particular moderator action. Privately, though, I would ask him to justify the action and give me sound reasoning. If we still disagreed and I thought it was important enough, I would involve the other mods. Presumably, the majority of the mods would then make the decision to keep the action in place or undo it.
3 When you see a question or answer with major issues, e.g. argumentative or poorly-written, what tool do you reach for first and why?
If I were not a mod I would immediately choose to vote to close. Then I would inform the user why in a comment. I would then make it a point to see if the user changes the post in the next few days. But as a mod I need to consider that my vote to close is a power vote. It would have to be bad enough were I cannot see good answers coming from it. I would, of course, still comment on the issues.
4 Bearing in mind that this site is about Christianity, but not a Christian site, how do you intend to remain as objective and non-biased as possible when evaluating the contributions of users?
I'm here to learn too. Even if I think the viewpoint being represented is not God's Truth I will still be happy to learn the viewpoint. "I am happy to consider completely rethinking my beliefs because after the fear of knowing nothing wears off I can begin a new life filled with the excitement a child gets when playing with something for the first time." That is from my profile. After that, the factuality of the post is very important. Even if the new user thinks they are representing a viewpoint correctly, I will act to correct or remove the content if I think it is incorrect if they cannot prove what they are saying with sources.