oz, IMHO, "B" is the best route to follow except in the case of a profanity being used. As a moderator, I totally disagree with the use of "A" for normal moderation practices, especially when it comes down to keeping a thread on topic.

When a topic is totally off topic for that board, I am in favor of locking and moving it to its correct home with a explanation of my actions. Unfortunately, there are several people on the DL board that are opposed to moving off topic posts that do not relate to DL to a more appropriate home. They challenge the moderators on that issue on a regular basis.

As a sidebar, one of the largest challenges that the moderators have to face on a regular basis is the presence of trolls on the boards. They intentionally post with a mission to incite flame wars and offer nothing that can be construed as a positive contribution to FT. Unfortunately, they usually manage to stay on the correct side of the TOS, and we have our hands tied as a result.