The Off Topic rule is, not that there is an On Topic element in the post, but is there "any" Off Topic portion. Off Topic, in any portion of the post makes the post Off Topic. That's the way Off Topic was explained to me by Admin. Unfortunately this rule is strictly enforced at the discretion of individual Admins.
With all of the new posts on the site and hundreds of messages for Admin to review throughout the day, our focus is on egregious violations of the rules here. Friendly, non-inflammatory, off-topic posts are permitted to allow for the ebb and flow of typical human interaction. Admin generally will remove posts of this nature when they are excessive and the noise drowns out the signal. Otherwise, our time and efforts are expended on the more material and egregious violations of the Terms of Service.
Friendly, non-inflammatory, off-topic posts are permitted to allow for the ebb and flow of typical human interaction. Admin generally will remove posts of this nature only when they become excessive and the noise drowns out the signal.