Simon, I agree that a poster's history (here and/or elsewhere) is very relevant, as has been clearly shown to me, on this db, in just this last month.
One thing I'm asking myself: Am I responding (or editing, or deleting) simply because I've come to dislike this poster? Or, do I refrain from editing or deleting simply because I've come to like this poster? If I'm "moderating" based solely on my "opinion" of a poster, is that wrong? (I don't think so) If I'm not willing to admit that to myself, and acknowledge it openly, am I wrong? (I definitely think so) Again, this is all within the ethic of this forum.
It's a hard call, a hard call indeed. imo, not an easy question to answer, nor an easy answer to live with.
Craig