I believe we are in a different fly way HCM, But it suprizes me to hear how weary those snows are for you, i suggest changing things up like i have my sets and color phases and using a single mouth call and a couple of baloon decoys. I have hunted this way and in late season hit the birds with great sucess in the morning and evening of the same day on the same feild the again the next morning in that same feild. I think the birds in my flyway must not get the same pressure either that or they are all inbred and retarded as i would not decribe them as hard to kill the exact opposite. They come in wanting to die for me at least.
I know the kind of destruction they can do i have seen pictures of the over grazed tundra where they nest. Hopefully the dept. of Nat. resorces increases the limits.