If it is obvious that a thread is causing offence then it is probably wise not to continue with it but it is difficult to see how subjects like for example politics and religion can ever be discussed because these two areas in particular can become heated. 

I suppose it depends on what NDY members want.  A place to just pass pleasantries or a forum to discuss all sorts of issues including those which may cause some ruffled feathers?

Often it is opposing views which are most interesting and it only becomes unpleasant when exchanges cross the line and become personal.