I think we came to a decision a while back where we decided that unless a seriously abhorrent comment was made that we would just lock a topic. The invisibilising is used by the mods to some extent still, but we found that members preferred a lock rather than seeing the posts disappearing. Hence we tend to go down this route, preferentially.
If a topic is locked you are more than welcome to start a fresh one, though, TOS violation free of course.
Hope that explains things for you.