Dave, I'm sure your last couple of paragraphs cover the majority of the more convoluted responses. A large number are "look how clever I am" posts, either for XP or community recognition. There is a small subset which are really sub-conversations, where the reply is directed more at other posters in the thread than the original question. Like any good party conversation, these can diverge wildly from the starting point. Unfortunately, there is no good way for them to go off into the kitchen.

The mechanism which seems to be in place to police the zanier posts is, again, XP. The problem is that node reputation is not knowable unless you have already voted on the node or it is a best/worst node. This prevents bias on the part of the voter, but also withholds the critical judgment of PM from the original poster. This reduces the effectiveness of the forum.

Perhaps if there were just a hint of the regard in which a node is held. If <0 nodes were so flagged in their headers, and highly ++ nodes (say, above the current weekly average) were positively marked, it would give the less informed newbie some insight into the experts' opinion of the answers presented, and not just a byzantine collection of perlish punctuation.