Leadership can not be underestimated, it starts at the top with Sing and down through the Coordinators and position coaches.
On the field, leadership on offense starts with the QB. Without a leader at QB, you don't have offensive leardership, period. Guys like Gore and VD are in essence assitant leaders, but the QB has to be the leader.
On defense, leadership can come from any of several positions. I don't mean simply who makes the defenisive calls, that is almost always an ILB.
I would take any comments Lott makes about leadership as the gospel truth. He is perhaps the best leader this team has ever had.