Perhaps, instead of removing the post, the poster could be given a warning and if the post is too far off topic the warning could include a reminder for other posters to refrain from replying to that post.
If the poster continues to ignore warnings you could invoke a suspension for a day, a week....or whatever.
If people ignore the warning to refrain from replying, then they could be suspended also.
That way the posts won't be removed and others can follow what's going on.
I'll talk it over with CTD and Russ. Remember the posts are not deleted Linear, they're still retrievable. They've been moved into an archive.
It is also possible to edit a person's post. So if the rest of the post is sound, then I'm thinking a mod can edit the particularly problem out and put in the reason e.g. "edited for....." and inform the poster with a warning also.
Moving an entire post is pretty drastic, but sometimes it maybe necessary to keep the thread as clear as possible if it's not contributing to the topic and maybe a source for retaliation. Yes I can put up a warning, but it's still a diversion....we'll see how things go.
Thanks for the suggestions.