I propose that all FORUMS have an OFF TOPIC button added. When you are reading a message that IYHO has no content related to the original topic, you just click it. The button has a resulting number next to it indicating how many readers consider the message OFF TOPIC.

or



???

kind of like the "Was this review helpful to you?" buttons on amazon comments?

unfortunately most of the time it appears that they are used primarily to show agreement or disagreement with the contents of the post, rather than the helpfulness of the post itself.

And what difference does it make? Like a good many fine conversations, subjects tend to drift. They can still provide useful information and insights. About the only drawback I can see is that retrieval of that information might be difficult if you are searching based only on thread titles.....