Thanks for resurrecting your excellent and well-written thread, jrp. And thanks for the kudo, hoodlum. The reason I like creating these what-if scenarios and asking for your thoughts is that, since they're all hypothetical, no answer can be wrong--everyone's input is valid.

I briefly considered an alternate scenario: What if Barzini knew nothing of Tessio's plot to kill Michael? What if Tess kissing Barz's ring at Vito's burial was just a little exchange of pleasantries designed to make Michael believe that Barz "wanted to talk"--the better to convince Michael and his entourage to leave the safety of the Mall and go to Tess's territory, to be killed by him? But, I rejected it because Tess had acknowledged that Barz was stronger than he. And, since Barzini had been chiseling Tessio's territory, Barz would interpret Tessio's coup d'etat against Michael as preparation to take the territories back by force. Barz would prepare for war--and since Tess's top priority after killing Michael would be to consolidate the remaining Corleones behind his leadership, the last thing he'd need would be a war with Barzini.