An Answer To My Question
Party of the actual question that commenced this thread was if there was any reason not to keep a home defense 870 with a full tube and a partially open action showing a round on the carrier (I have been calling it the elevator). When I went to reduce my full tube by one, as per Lee and Dave, my 870 answered my question. If, instead of sliding the forend to the front you pull it back just a bit, your action is locked up when a round spits out of the tube and onto the carrier to jam up against the round that had been sitting on the carrier. That round is held in the action by the extractor and it can be cleared with some work, but I wouldn't want to have to do it in an emermency situation.
So the way I am keeping my 7 round 870 (6+1) is bolt closed on an empty chamber, hammer down, safety on, and 5 shells in a 6 shell magazine. Cruiser ready. For my household I think that the best balance between readiness and safety. If I lived near Fort Apache, I might go with a full seven but thankfully I live in boring middle America. IOW, like Dave McC says, YMMD.