Sue , sorry to hear about Bob.
I don't think the original post here was requesting that no off topic posts should be made, I think it was asking that they not be mixed into a mostly medical or article thread discussion. At least that was how I read it...
I know when a thread gets very long with many replies it will tend stray off from the original, it just happens.
On some of the other forums if a discussion gives rise to another thought or idea one of the members usually will post a note saying
" I think we need a new thread for this topic - I'll start one"
and they just do that, it seems to work well.
Sometimes when there is a very informative medical or article thread members will ask me to place a link or copy into the sticky thread on that forum- so it's easier to find if needed.