Nemo:
Posts are in violation if they:
• Are flagrantly violating Bob's rules.
• Are unable or unwilling to stay on topic.
• Have no apparent goal except to disrupt and annoy.
For instance, posts that are excessively profane or vulgar can be judged as violating Bob's rules. But remember that not all moderators will agree on what constitutes "excessive."
"Off topic" is, as it says, off topic. Off topic posts should be deleted if they are distracting from the general conversation.
A post that exists only to insult other members can be judged as having no apparent goal except to disrupt and annoy.
Moderators may use their judgement on what to delete.
My preference is to be tolerant, within reason, so as to not kill healthy debate.