I, amongst many older blues hated that banner more than anything. It was always there and every match they were on tv, which was often, the cameras always panned in on it. I actually don't remember when it first appeared but it seemed like it was always there, which for most of their successful period it was. More than anything it evoked real hatred for them that went beyond the normal local rivalry you get in most cities. It was below the belt and breathtakingly arrogant. For me it crossed the line and the fact the hierarchy at that club allowed it's presence made me detest them all the more.
That is why for all his faults which have been revealed since he left Mancini will always be a hero to many. He hated that banner too and said he would tear it down and he did.
I would actually have that banner or a picture of it as part of our history. Just before every derby match I would show the players it and explain the story behind it. Team talk done.