While I have refrained from adding to this thread until now, I will try to address this specific point.

I am thoroughly in support of Doc's practice of adding to an existing thread when there is new information on its topic rather than starting a new one. It is far easier for me, at least, to find information on a topic when it's all in one place rather than reading a new thread and hunting for its predecessor or reading an older one (that was bumped up by a recent post by someone else) and wondering if there might be a news update posted someplace. I believe most people who want to read about a topic would agree.

The only downside seems to be that one might open an older thread that has just been updated, thinking it is a new one. However, good topic lines (most of his are good) make this unlikely. If one is interested in a topic, and the thread contains new information even if it was started some time ago, it's not a problem. If one is not interested in the topic, one needn't open a thread even if it looks new.