Swinging the gun on waterfowl

[kt]

I am looking for insight as too the best way get a bead on birds when you hunt a variety of species. I spend the majority of my season hunting honkers that are locked at 10 yds or mallards with their feet down at 20. In such situations i can usually just get a bead on where i want the steel to go. The problem lies in when i attempt to change it up and hunt big water or a river. The first dozen or so divers to come by are safe by the time i establish the right lead. Crows flying with the wind got me this weekend. Do i need to go back to the "swing through the bird" way? I am so used to established leads on slower birds.
kt