I wouild think that coming at you would be closer, open choke, going away if you missed or shooting at the one that flarred would be the fuller choke. This is with double triggers of course.
Why did you differenciate between ducks and doves with different chokes, it is still overhead and behind.
As far as the lead, all depends on estimated range as to what to fire first.
Two birds flying together, aim inbetween, no kidding. I think it all depends on your natural swing, right to left or left to right as to which to shoot at first.
