I was sitting right besides one of the anointed, a personal friend of mine, and I saw him break of only one piece before passing the plate to me. He also took one sip of the wine . This was in the 1970s.
If everyone in the congregation were of the anointed this would change how it's celebrated. For example, if you were to eat the whole bread before passing it it would make the meeting much longer in duration plus the plates would have to be refilled.
So I wonder what arrangements they had in the days of Russell and Rutherford? Did they sit at the table and have a proper meal out of the emblems? This would approximate the original Last Supper.